M1007 - CUCV Suburban Clone Build Thread

[Barrman]

I have the oil not going through the radiator. I installed one of the big coolers that Leroy's Diesel sells along with the braided steel lines to connect to the engine. Since the GEP engine has the bigger oil ports on the block. The stock 6.2 hoses/lines wouldn't have worked. Even though I am not using it, I still wanted my radiator to have the oil cooler ability. You never know what the future holds.

Oil temperature taken at the block from the little port that could be used to feed a turbo normally is in the 160° to 185° range. I have never had it higher than 195° and that was in stop and go traffic with really high outside temps.

I run the transmission fluid to the radiator, then to the biggest cooler I could find that will fit in front of the radiator next to the oil cooler, then back to the transmission. According to the TCM which takes the fluid temp inside the transmission. In normally cruise at 163° on hot days. Any time spent driving below lock up speed puts me in the 174° range. I have had it as high as 191° when pulling in stop and go traffic with high outside temps.

I was very glad I ran the transmission through the radiator back in January. I drove a few hundred miles with outside temps at 24°. The transmission fluid went up to 145° and stayed there on the open road. I think the coolant kept it that warm. Engine oil temps were around 165°.

 

[Barrman]

I think the truck for the first time ever is now leak or even drip free. The original to the truck power steering box has leaked out several seals and is pretty loose. I have not found a new replacement that seems to me worth the price they want for them. I really don’t think a parts store rebuild is going to be an improvement in steering quality. So I turned to my “parts depot.”

I pulled the steering box off a 1989 K10 Suburban yesterday that had not very many miles and no visible leaks or even dirt on it. I had driven the truck when I brought it back from Warthog a few years ago and remember being impressed with the tight steering. The old Cowdog box went on that truck so it could still be moved around easily.

Since I had to remove the intermediate shaft to get the box off. I figured this was a good time to get rid of the rag joint. I researched the Jeep XJ shaft conversion and decided to try it. Basically, the top of the line $300 plus aftermarket shafts are u-joints at both ends of the shafts. So is the 88-94 XJ. Used they are just a few dollars. New, around $90. Even new, they are tremendously cheaper than purpose built for the truck units. I got a new one from amazon.

I dont know which part made made the most difference. But, WOW! The truck drives totally different. No more road wander, no more sawing at the wheel in a cross wind. I put around 100 miles on it yesterday. 70 mph on a twisty highway with oncoming traffic and people in the lane next to me in a 20 knot cross wind. I was able to pick exactly where in my lane I wanted to be and stay in that spot for the first time ever in this truck.

 

[Barrman]

It has been hot here. HOT hot. Perfect time to test out the cooling system. However, I just haven't wanted to abuse the truck for no reason. Yesterday I had a reason. Colton is back at A&M for the fall semester. He called to tell me the drivers tie rod pulled out of the steering rack on his Jetta yesterday afternoon. Tie rod looks good, but all the threads on the rack are gone. He has had a thunking noise we couldn't figure out the past few thousand miles. He found it. He was able to get the car to a parking lot where it could sit until I got there.

Anyway, I needed to pick up the VW and get him something else to drive after work was done. 2,000 pound empty car hauler hooked to the Cowdog with 104° outside temps when we started. Jennifer just drove the Honda. It is so low slung it drags on the trailer and I didn't want to mess with loading and unloading it.

70 mph in OD with the Torque Converter locked pulling the trailer had me up to 205° and down to 198° when off power or below 60 mph. I was impressed. a pair of hills caused long runs of 6 psi boost and around 1000° EGT in 3rd unlocked. Those got me up to 210° but it went right back down to 205° within seconds of the power getting reduced.

I have wired up the switch to change the Transmission Control Module to different settings while driving. I have the other program all set up to be TC locked in 3rd gear for better engine rpm without cooking the transmission at 60-65 mph. I never went to it because I wanted to see how it did at 1800 rpm and except for those two hills, it never left OD and locked. Good with me.


We got the Jetta loaded up around dark and then I could really tell the difference the radiator has made. Towing the same car in the same heat back in May as described a few post up. I couldn't go more than 50 mph without hitting 210° on the coolant temp. Last night I set the cruise at 65 and stayed around 205° except for the hills.

Big hills that caused it to unlock and grab 3rd put me up to 1100° and 6.5 psi boost. (Highest I have ever had for both) Followed by coolant spikes at 212°. Right back to 205° within seconds of power off again though. Something that didn't happen with the old radiator. It used to just keep creeping up and up and up. Now it spikes and goes back down.

What I wasn't suspecting was the sneaky hills. Not big enough to cause it to unlock or grab third or even throw a lot of boost in. 29%-32% throttle position sensor angle was normal with car on the back at 65 mph. 600° EGT and 1.5 psi boost was cruise readings. I would notice the EGT rising, look at the TPS and see we were at 50% or so and the boost would still be below 2 psi. TPS would stay steady and the EGT would keep going slowly up. I would break cruise when it got to 1100°. Both on hills a few miles from my exit so I just watched what was happening knowing I would be on back roads in a few minutes. The next time I pull in high heat, I will switch the TCM program and run 3rd with the lock up option. Then try to find the happy speed for that combination and see if the sneaky hills are taken care of.

Oh, sustained EGT above 900° on the sneaky hills caused the coolant to spike at 214°. Off the power, slowing to a stop sign had me at 198° before I could get going again. The cooling combination is working! Working very well in my opinion.


I had also not driven the truck with a trailer since I did the XJ steering shaft swap and steering box replacement. Much, much better. I was on oil field truck rutted 4 lane highway at night with a truck narrower than the ruts and a trailer in the ruts. All while passing and getting passed by the oil field trucks. I had to pay attention, but it was a relaxed drive compared to "wwwwoooooo, oooohhhhhh" as it used to be.

 

[Barrman]

A few months and a few more things learned.

I have another 600 or so miles of pulling a loaded trailer now. As mentioned above, the steering shaft and steering box swap really helped. It was still kind of iffy feeling at times though with the loaded trailer. I know the 4x4 3/4 ton Suburban's have a pretty low trailer rating compared to the 2x4 Suburban's of the same year. I was starting to think maybe I had found the same thing Chevy did when they put the lower rating on the K trucks.

I have been messing with the front tire PSI for 18 months now trying to find the right combination of handling, tread contact with the road and bump absorption. I thought I had the best I could get at 39 psi before I changed the steering stuff. Turning response was so much better that I decided to go up to 41 and see what that did. It made it squirrelly and only the center of the tread was touching the road. 38 is my test psi currently. Much more stable, but still not getting 100% road contact and a bit harsh of some bumps.

Anyway, while messing with the front tires I decided to check the rears. I had them at 39 as well. I had to go to San Antonio and pick up a vehicle a few weeks ago and decided to try the rears at 45 psi. That combined with the bias ply trailer tires at 60 psi made for a very ruff and uncomfortable drive down. Jennifer was starting to get motion sickness. A 3,500 pound car on the trailer and the truck drove like it was on rails with super comfort. I need to start carrying my CO2 tank on trailer trips to move the pressure up if I have to drive out with an empty trailer I guess.

Then I took it camping with my Trail Life Troop this past weekend. 3rd seat removed, loaded M101 with a cargo cover attached and kids pilled in with their gear. We had to go 25 miles down a paved back road to end up in a field of a local rancher. I was actually kind of anxious about the drive. My 6.2 powered M715 can't pull a M101 with the cargo cover more than 42 mph because of the air brake effect. My stock M1009 tops out at 48 mph with the cargo cover attached. I didn't think the turbo 6.5 would have issues, but you never know until you do it.


I was able to run the speed limit up hills with a slight head wind all the way. But, 60 mph required 3 pounds of boost when normally it stays on 0 except when climbing a hill. The turbo knew the cargo cover was on. We got there fine and I got stuck turning around. I used a spot where a few round bales had been eaten down to try and turn after the kids had gotten out. It was a slimy goo that wouldn't let me turn the truck. The M101 didn't really help much either. I was able to self extract in 4 low and sawing the wheel back and forth with lots of throttle to make a huge turn in the pasture mud hoping no mesquite tree's were hidden in there.

That was Friday. We had a few inches of rain come in early Sunday morning. I was parked nose up on a slight incline perpendicular to the gravel ranch road needed to get out. 2wd didn't even move me. I actually check the trailer brake handles as I was locking my hubs in because I just didn't move in 2wd. 4wd wasn't much better. I couldn't make it 10 feet up to the road. I did manage to get the truck turned enough that someone on the road could pull me and I wasn't at an odd angle.

That is when I realized the one good thing I have ever thought about the M1009 tailgate. An almost jack knifed to the passenger side M101A2 trailer behind a Suburban means the barn cargo door will move about 5 inches before it hits the top of the brake actuator if the truck has sunk down a few inches from spinning the rear tires. Darn.

Of course, my tow strap was next to the driver side cargo door. I went over all the gear from the front and got it out. A pull from another truck to get me rolling and I was able to climb the rest of the way out myself. This was a slimy puddled grassy goo that was hard to walk on. I don't think lowering tire psi would have helped all that much. Every vehicle there was 4x4. Only the people with mud tires were able to get to the road by themselves. All of us with all terrain tires needed a pull. I was also the only one with a trailer attached which is a big huge land anchor anyway. I am now convinced mud tires will be what get put on when I have to buy new ones.

The rain also brought a 25 mph north wind. I had to drive straight into it to get back to town. I was able to hold speed, but 4 psi of boost was now required to do it. I sure love this turbo!

 

[Barrman]

More Cowdog updates.

Life changes have made it so the truck really doesn't get used much at all. I built the thing as a daily driver for our 10 mile round trip commute, trailer puller and camp trip command vehicle. I finished it 2 years ago. It took about a year to sort out all the "I will get that later" issues. Mostly the very well documented engine cooling system issues. Colton went off to college 3 months after I got the truck done which really cut down on the camping and family road trips to the wild.

Then, Jennifer went and got an infected cut on her right foot. It just wouldn't heal so they put her in an isolation cast. The cast was made like the old ones with plaster. The 35's on the Cowdog make it just a hair too tall for her to get into easily. I carry a foot stool that she uses to get in with. The problem is that she isn't patient enough normally for me to stop the vehicle, get out, walk around, get the stool out of the back and then get to her door so she can step out. Nope, she just slides off the seat and CRACK! goes the cast. After several cast over 4 months were broken his way. I just made excuses about why we should drive the Accord to work instead of the Cowdog.

The Accord is a perfect appliance. But comfortable and fun to drive are not on the list of things I like about it. I went looking for a fun, comfortable and cheap car to take up the daily driving duty. I settled on a broken BMW E46 330 in San Antonio last fall. The Cowdog is a great long distance vehicle recovery platform. Everything I hoped for during the build it has turned out to be. Comfort, highway speeds, pulling power and long legs with the 40 gallon fuel tank and around 15 mpg with the trailer empty. 13 loaded. Unfortunately, the BMW had more things wrong with it than I knew about and didn't know enough to find on my own. It went away for about what I had in it.

Jennifer spent about 2 months out of the cast before she broke her left foot. Back in a cast and back in the Honda for us starting last October. She is now in a fitted plastic boot/cast because she keeps re breaking the foot. The Cowdog got used to go recover a broken BMW E39 525 Touring 5 speed and a parts car to repair it over the winter. While I was making a working car out of the pair. Jennifer went and got her cast stuck under the brake pedal of the Accord in the pharmacy line and she totaled the Honda. The Cowdog got to haul it to it final resting place in March. This was her 4th totaled vehicle since we have met for those of you who know us and are keeping count.

While hauling the Honda to College Station the Cowdog just didn't feel "tight." Maybe it was because I had been driving rack and pinion steering vehicles just about all the time the previous few months. I really didn't worry about it. When we dropped off the car we had a few errands to run and I dropped the trailer at the body shop. I took a wrong turn leaving and varied from my normal turn around technique of backing in. There was traffic and I nosed into a concrete drive way and turned the wheel lock to lock with the brakes on. A very loud thunk came from the front of the truck. I backed out and got headed the proper direction. That was when I noticed the steering wheel was turned 90°! AAAHHHH! I very slowly and carefully slowed down and eased into a parking lot.

I got out and could find nothing loose, wrong or weird. I turned the wheel a few times with the brakes on lock to lock and got another thunk. I got out again and could not figure out the source of the noise or steering wheel difference. Whatever it was, it was popped back into normal position. I drove a little and checked again. It felt normal and looked ok. Being 70 miles from home, we grabbed the trailer and taking back low speed roads made our way home without incident or it happening again.


I put a wrench on every part that moves in the steering and suspension system. Everything was tight. It is very difficult to hear things standing next to a running 6.5 and reaching in to turn the wheel. I could not duplicate the noise or "steering system jump" without the engine running and brakes on while sitting on concrete. I finally noticed when I turned the wheel with the engine off the tire was rolling. It was rolling a lot. I went and did the same thing on a M1009 which has the exact same system and the tire didn't really roll. Progress. I needed Jennifer to move the steering wheel while I was laying under the front end to figure out the drivers side leaf spring U-Bolt were loose and the axle was shifting back when turning left and shifting forward when turning right.

The nuts were loose. Not falling off loose, but all 4 required many turns to tighten back down after I made sure the axle was back in the centering pin slot. The passenger side nuts were not as loose, but they weren't all the way tight either. I don't have a memory of using a torque wrench on them during the build. I do remember tightening them up. I don't remember torqueing the wheels on the last time I had them off either, but I know I did. So, I don't know if this has been loose the entire 8,000 miles I have driven the truck or just something that worked its way loose. Either way, they are tight now and part of my checklist of things to look at when under the truck.

It drives really, really great now by the way. So great I was going to drive it 1,500 miles next week starting Saturday taking my Trail Life kids out to west Texas for mountain climbing and such. Except, several of the boys earned their way into summer school and have to be there I just found out a few days ago. No trip.


Even though she has proven to be a person that should not be allowed out of the driveway in a vehicle. Jennifer does need to drive herself and since everything I have besides the Cowdog and M1009 trucks are manuals. We had to replace the Honda. We ended up finding a high mile Outback owned by a guy with OCD. Which is the perfect kind of person to buy a used vehicle from. Everything that wears has been replaced in the past 30,000 miles. She likes it and I haven't decided yet. However, when we got invited by her sister to come stay at their place in Colorado for a week next month. I thought "Finally, a Cowdog trip." But, it makes more sense for just the two of us to take her car. We will see.

 

[Another Ahab]

More Cowdog updates.

Then, Jennifer went and got an infected cut on her right foot. It just wouldn't heal so they put her in an isolation cast.

Jennifer spent about 2 months out of the cast before she broke her left foot. Back in a cast and back in the Honda for us starting last October.

Even though she has proven to be a person that should not be allowed out of the driveway in a vehicle. Jennifer does need to drive herself and since everything I have besides the Cowdog and M1009 trucks are manuals. But, it makes more sense for just the two of us to take her car. We will see.

Poor Ms Jennifer! I get that she needs to drive:

- Because for a while understandably she sure is not wanting to do a whole lot of WALKING

Sometimes, you have no luck at all if not for bad luck (it can happen to any of us).

Good Luck to Ms Jennifer!

 

[Barrman]

I had a really weird drive home yesterday. Jennifer and I went to Cabellas about 70 miles away. About 20 of those miles were done at 80 mph on the toll road with that speed limit. 2300 rpm, 3 psi boost, 700° EGT and 198° coolant to hold that speed in a pretty hefty head wind. All was good in my world.

We made a few stops on the way home. 20 miles out with groceries in the back and full dark. We were cruising along at 60 mph. Which should be around 1700 rpm. Except I was startled to see we were at 2000 rpm on the tach. The transmission controller also said 2000. Thinking I had put it in drive instead of overdrive. I got off the power and went a click left on the shifter. The controller said I was in neutral as did the free revving engine when I applied throttle. I went back to what must be OD and now was showing 2500 rpm at 60 mph. Uhoh!

The controller said I was in 4th gear with a locked torque converter. Obviously, it was lying to me since maintaining 2500 rpm had our speed down to 50 mph. Transmission fluid temp was steady at 137°. Well below normal temps. Passing cars lighting up behind me showed no smoke. It was around now that my mind started to recognize a background noise I had been hearing all along but didn’t pay attention too.

The noise seemed to be coming from the drivers side firewall/door hinge area. It was getting louder. My rpm kept creeping up so I kept slowing down. Middle of nowhere country road in the dark. 8 miles from home I started calling people that might be able to tow me home since Colton is off in Arkansas riding his mountain bike in the mountains.

I was pretty convinced my torque converter was the noise and the slip causer. But was really puzzled by what the controller was telling me. Trying to keep the engine below 2500 rpm had me down to 3rd gear and 30 mph. But the fluid temp was still steady and a car catching and passing me showed no smoke coming from me.

4 miles from home I was down to 2nd gear, 2500 rpm and 15 mph. 2 miles out I had to make a sharp 100° turn and climb a hill. There was no way to carry any speed for the hill through the turn and I was worried about making the hill. The grinding noise was getting louder by the minute too.

Halfway through the turn the noise abruptly stopped and I lost power steering and voltage. Obviously, my serpentine belt had come off. I also lost my tachometer. Knowing my water pump wasn’t turning either I hit the power in hope that the transmission might have enough left to get me over the hill before I turned off the engine.

The transmission dropped to first, shot us forward, hit second with authority and threw us over the hill while hitting third firmly. Whaaaaat? I shut down the engine when the coolant hit 210°. We coasted down the hill and almost over the next one. While coasting I was trying to figure out what link there was between a belt driven accessory and the transmission which seemed to be working perfectly now. I couldn’t figure one out because there isn’t one. But I kept wondering.

I had to start the engine twice, put it in gear and accelerate up a grade to make it home. Once stopped I got out to look. Opening the hood showed nothing odd except for the missing belt. I turned the power steering pulley and it felt ok. When I touched the alternator pulley it fell off in my hand! The outer rim and bolt center were there but nothing else.

Then it all made sense. Even though I built the truck and wired the truck. I had forgotten the rpm signal comes from the alternator. I had also forgotten the transmission controller uses a tach signal from the input shaft for control purposes. But, the display rpm was tied into my dash tach. I had it in my head while driving that the display rpm was coming from the input shaft. I was wrong. As the pulley ate itself the diameter of the pulley got smaller and smaller. Increasing the rpm of the alternator with the engine going a steady speed. When I pulled the alternator off the front bearing was shot and it did want to turn.

 

[Barrman]

Forgot the picture.

I went down the road last night and recovered my still one piece belt and returned it with the alternator to O’Reilly’s today. Both had to be ordered. I should confirm all is well again tomorrow.

 

[sneekyeye]

LoL, my alternator ate itself in a similar fashion, but i was stuck at a stop light as the belt burnt itself off. Mine failed as one or two of the front ball bearings in the alternator lost a ball and the shaft dropped into the spot left by the open ball and suddenly locked up. After my belt shredded it was an otherwise uneventful drive home. New bearings and a set of brushes in both alternators and we were back in business.

 

[Another Ahab]

Forgot the picture.

I went down the road last night and recovered my still one piece belt and returned it with the alternator to O’Reilly’s today. Both had to be ordered. I should confirm all is well again tomorrow.

Glad you made it home alright.

That was SOME adventure for sure.

 

[Warthog]

Barrman it was great to see you the other day during the Covid event.

For those that say this thread should be in the "modified" forum, yes it probably should, but it was started by me before there was a modified forum and thus that is why it is in the regular forum. If the admin wants to move it then so be it. But if not it will stay here.

 

[Barrman]

Nice visiting with you as well Joe.

The Cowdog got to pull a M101 about 200 miles over the weekend taking Colton one of my old motorcycles. He needs a project now that online college is done for the semester and his internship got canceled. That truck loves to go down the highway at about 64 mph.

Last night I put the swing away spare tire mount back on. I need it there so I can look at how I built it 3 years ago while building a swing away water and CO2 mount on the other side. Going to incorporate the nifty surplus NATO can holders Mark was selling at the Rally a few years ago. Getting closer to Overlander ready again.

 

[Another Ahab]

Nice visiting with you as well Joe.

The Cowdog got to pull a M101 about 200 miles over the weekend taking Colton one of my old motorcycles.

Just call me "Drifting Dan":

- What kind of bike?!

 

[mkcoen]

Going to incorporate the nifty surplus NATO can holders Mark was selling at the Rally a few years ago. Getting closer to Overlander ready again.

Glad to hear someone is getting use out of them other than myself (also glad to hear Joe is still alive and kicking )

 

[Barrman]

I pulled the holder out of its original packing this morning Mark. It is going to work perfect. Once I actually have something I will post pictures.

1973 Honda 350four. I got it back in 1990, used it a little and moved onto muscle cars so interest got lost. I purposely didn’t mess with it once Colton was born almost 22 years ago. I figured me being around was more important than getting to hear that SOHC 4 sing at 10,500 rpm.

He will take his private check ride in 2 weeks so I figure he can think for himself and be aware of his surroundings enough to start riding himself. He has gotten it started but still has a bunch o do before it will go down the road.

 

[wheelspinner]

I pulled the holder out of its original packing this morning Mark. It is going to work perfect. Once I actually have something I will post pictures.

1973 Honda 350four. I got it back in 1990, used it a little and moved onto muscle cars so interest got lost. I purposely didn’t mess with it once Colton was born almost 22 years ago. I figured me being around was more important than getting to hear that SOHC 4 sing at 10,500 rpm.

He will take his private check ride in 2 weeks so I figure he can think for himself and be aware of his surroundings enough to start riding himself. He has gotten it started but still has a bunch o do before it will go down the road.

What a great bike!

 

[Barrman]

I have had the Cowdog on the road a little over 3 years now. 4 years ago when I bought the H2 wheels off Craigslist. They had BFG all terrain tires on them with reasonable tread. Except they were 2007 or date coded. I have needed new tires from the start but life kept eating the money needed to get them. Maybe I have too many projects as well?

Anyway with full summer here again I have been hesitant to drive the truck much above 40 mph. The old tires at 40 psi were rock hard, the steering was very darty if that is an actual word and the ride not pleasant. I put other things on hold and got a new set of shoes last Friday. Loud range E. At 65 psi this truck is now super smooth on good pavement and enjoyable on broken up back roads.

I did 300 miles today of mostly open highway 70-75 speed limit. 2 psi of boost with 650° EGT at 75 mph. This thing just eats the miles away now. I’m still waiting for a few parts to get shipped so I can finish the passenger side swing away gear holder. Once that is done. I think it will finally be ready for an Overlanding weekend trip once the weather cools a bit and I save some fuel money up.

I have no clue what mpg I got blasting along like that. I will fill up this weekend and hopefully it won’t be too bad.

 

[dougco1]

I have had the Cowdog on the road a little over 3 years now. 4 years ago when I bought the H2 wheels off Craigslist. They had BFG all terrain tires on them with reasonable tread. Except they were 2007 or date coded. I have needed new tires from the start but life kept eating the money needed to get them. Maybe I have too many projects as well?

Anyway with full summer here again I have been hesitant to drive the truck much above 40 mph. The old tires at 40 psi were rock hard, the steering was very darty if that is an actual word and the ride not pleasant. I put other things on hold and got a new set of shoes last Friday. Loud range E. At 65 psi this truck is now super smooth on good pavement and enjoyable on broken up back roads.

I did 300 miles today of mostly open highway 70-75 speed limit. 2 psi of boost with 650° EGT at 75 mph. This thing just eats the miles away now. I’m still waiting for a few parts to get shipped so I can finish the passenger side swing away gear holder. Once that is done. I think it will finally be ready for an Overlanding weekend trip once the weather cools a bit and I save some fuel money up.

I have no clue what mpg I got blasting along like that. I will fill up this weekend and hopefully it won’t be too bad.

It should be about time for a few updated photos of Cowdog now that it has new shoes

 

[Another Ahab]

They had BFG all terrain tires on them with reasonable tread. Except they were 2007 or date coded. I have needed new tires from the start but life kept eating the money needed to get them.

Probably for sure a dedicated thread here somewhere about tire life.

But being from the Typically Lazy School (TLS) of data-gathering:

- What is the general recommended anniversary milestone (+/-, dismissing tread wear as an issue) for replacing tires?

- 5 Years? 10 Years? "Depends"?

This might be a question with no single good answer, but you know, just checking for anyone's sense of expertise.

 

[Barrman]

Tire stores, tire manufacturers and the government all say 3-5 years is all a tire should last. Of course, they want to sell new ones or act like a nanny. So consider 3-5 years a minimum independent of tread wear for tire life If run at proper inflation with a properly aligned suspension.

That being written, nylon cord tires don’t rot or rust like other materials. So all of our military tires with nylon cords have normally a much, much longer life span. Environmental influences play a massive part in tire life. Direct sun light kills tires. As does a very hot road. Which is why I moved now in full blown summer.