CUCV questions.

[Ungoliant]

So I've been looking for a good off-road project, and I found a few CUCVs (Blazers and pickups) for sale, with the 6.2 Diesel.

1. What kind of issues are endemic to the 6.2 Diesel?

2. What sort of engine/drivetrain modification, if any should be done (other than your axles/driveshafts) for off-roading?

Obviously I'm a little new to this but I'm pretty interested, and I figured these vehicles would be a good choice for off-roading, I haven't heard anything bad about them, etc.

 

[4bogginchevys]

great vehicles for off roading, cant be beat......if your serious about off roading the 6.2 is not the ideal powerplant. If you know this going in to the deal you'll be very happy with the purchase. Not a bad engine, just not intended for that use other than minor stuff. Good luck

 

[Ungoliant]

I see. So what kind of powerplant should I look for, and what else would I need for a swap?

 

[4bogginchevys]

BBC or SBC

 

[91W350]

The 6.2 can do a fairly decent job off road, you just need to learn to use the low side of the transfer case more frequently than a BBC. One thing I always appreciated about the 6.2 was a very flat torque curve. They do not get to a point then light the tires up. I would say their main weakness is their limited rpm range. A M1008/M1028/M1010 is a below 55 mph truck, even with tall tires. They are geared at 4.56 and that is just too low for extended highway running. True, you can run them faster, but faster leads to cracks in the main bearing webbing in the block and eventually main bearing failure. The 6.2 engines in high geared half ton pickups, Blazers and Suburbans lived a long time. The ones in low geared pickups or one tons frequently died with less than 100,000 miles. I have read it is okay to run on the governor as it is a diesel and that guys have been running theirs 65 with no issues. I wish them the best of luck. It is true that the Cummins can be run on the governor and not be hurt. I would not do that with a Powerstroke or the older GM diesels. I am not too sure a guy wants to treat his Duramax that way either. These engines will scream rpm wise for a diesel, much higher than a farm tractor or over the road diesel. Glen

 

[kenny]

Low power is about it but if you know offroading Carbs Suck on a Gas engine when you go strait up a cliff to the point of almost backfliping the carb will flood out and kill your engine and leave you in a messed up spot.
With the 6.2 diesel it will never happen.

And 91W350 is right on the 4low part. 4High is more for flat land mud or snow and not so much climbing bolders or big hills

 

[Ungoliant]

I see, so as far as going all out with an off-roading project, it's probably better to get a different engine at some point? Or can these engines be modified safely to accomodate a turbo? I read somewhere that their cylinder walls are too thin to handle a turbo.

 

[ken]

They can handle a turbo just fine. And can be made to prouce about 200HP. But you have to ask yourself. What kind of off roading will you be doing. If your just throwing your truck into mud holes then the 6.2 isn't a very good choice. You would need high RPM HP for that and the 6.2 doesen't like to turn alot of RPM's for very long. It's also heavy. and loves to sink into mud holes. If you are running trails and climbing hills the 6.2 will really shine. Plenty of low end tourqe and can handle steep grades without running rough. not to mention it will run all day in the woods on 5 gallons of fuel.

 

[Tanner]

They can handle a turbo just fine. And can be made to prouce about 200HP. But you have to ask yourself. What kind of off roading will you be doing. If your just throwing your truck into mud holes then the 6.2 isn't a very good choice. You would need high RPM HP for that and the 6.2 doesen't like to turn alot of RPM's for very long. It's also heavy. and loves to sink into mud holes. If you are running trails and climbing hills the 6.2 will really shine. Plenty of low end tourqe and can handle steep grades without running rough. not to mention it will run all day in the woods on 5 gallons of fuel.

Weight-wise, the 6.2 is comparable to a big block Chevy motor...

'Tanner'

 

[Warren Lovell]

I have an M1009 for my daily driver and took it out on my desert (so Cal) trips for years. Nothing hard regarding offroading, but comfortable. The H1 Hummer is amazing off road and has replaced my M1009 as the camping vehicle.

Maninence-wise, the M1009 has given me no problems except for needing to replace 6 year old batteries and a power steering pump, and putting 33" tires on her.

The H1 is a vehicle you have to stay on top of with maintenance. Geared hubs, sensors, PMD's, injectors, glow plug changes...all the normal diesel stuff is more difficult to access on a turbo H1.

So - for mild off roading an M1009 is great. Anything more - get a humvee.

 

[Cucvnut]

most people on here install BBC's including my self. you only gain about 1000 rpm with it but it helps and when you go to bigger tires you can go a little fast on in the free way

 

[gwag]

it depends what type of offroading your planning. I love my 6.2 and it probably runs poorer than most. I mostly crawl up ravines, hills, dry creek beds, etc. (no rocks here) It's great for this low speed, low rpm stuff I just put it in 4LO & go & it runs the same at any angle no matter how extreme. I've had it on it's nose so bad I had to push hard against the wheel to stay off it.
I would say the biggest drawback as far as off roading is the steering these rigs need the crossover set up as they have no steering when the drivers side front gets drooped out.
When I set my M1028 up I was concerned about fuel capicity with the stock 20 gal tank but have had it out 2 solid days and it burned less than a half tank your not going to do that with a gasser.
I would shy away from the M1009s unless you have to have the cab room the pickups already have the HD axles and low gears.
For trail runnung & crawling the diesel will work great but its not for a high HP or high RPM application.
Mine is 4" ranchos in the front with a shackle flip in the rear running only the top 5 leaves. 37" tires, hyd winch (never used yet), shortened bed 14" between the wheels & taillights. Very capable rig that's hard to stop!

 

[91W350]

These guys covered it pretty well.... if you want to get into axle deep gumbo and spin a set of 38" tires 40 to 60 mph to keep the tread clean, you have the wrong engine. That is big block power and nothing does it better. If you are like me and try to avoid the super deep soft mud and prefer trail running, a little rock crawling and climbing steep slopes, the 6.2 is perfect. If you want to scream across the dunes on a set of paddles in some soft sand, better fork out the dough for big power. Glen

 

[OL AG '89]

CUCV power vs. reliability

I bought my CUCv for the reliability of the 6.2. I don't plan to get into the knee deep thick stuff, but if I do, I have a 10K winch at the ready..... no use blowin motor getting unstuck.. My other reason is the "keep plugging fuel and air and it'll run forever" theory of going deep into rivers.... I know, the electrical in the cab may suffer, but the engine doesn't need electrical once it's running.... unlike a SBC or BBC..... I will try this theory out in the near future......
of course if I had $30K extra laying around I would also opt for the H1, but not practical use of kids college funds..... although..... yea, never mind
As far as the strength of the running gear, the P/U has stronger gear, but then again How you use the vehicle determine the requirement for "crusher" gear

 

[Warren Lovell]

The H1:

1)I backed into a parking space between two cars, behing my house. I'm talking to a friend and pull out...taking the car on the rights bumper and taillight out. My H1? the side rail had a smudge on the paint!

2) dropped off the kids at the ex's...back out, didnt see the Lexus that just parked across the street. I put the driver rear fender of the Lexus into the trunk before I felt the H1 squish it. the H1? No damage!

3) Dropping off a video at Blockbuster. A new Volvo pulls in right on my bumper, parks in a red zone and driver gets out to drop off video. I can't make the left turn into the space, so I back up...put the Volvo's grill into the radiator!. The H1? A little bit of paint transfer to my hitch!

The M1009: I'm at a stoplight. A guy on a cell phone rearends me. His bumper is destroyed, along with his grill. The M1009 got no damage. The two cargo loops and pintle hook left nice holes in his bumper.

I think both these vehicles are rugged. I wish someone made a roll cage for the M1009. That will be the last project for her.

H1 wagon got a rear view video system, but is still too high to see the low cars that come up next to you.

 

[gwag]

the M1009s are cool but if your gonna run bigger tires axle upgrades are in your future!

 

[gwag]

Warren I bet your insurance carrier is real proud of you!

 

[Belteshazzar]

how many of the trucks were made?

 

[Ungoliant]

Well I was looking into mudding. So I suppose the 6.2 is a bad idea, maybe I should look for a different vehicle?

 

[4bogginchevys]

Warren, you forgot to mention that was just last week.....