front suspension mods AKA - ride improvement mods AKA - butt happiness mods

[Buffalobwana]

Funny thing about this thread being here now.
I weighted my truck by the axle on the way to the spring shop this morning.
They are going to remove the rear springs and reduce the capacity so it is more in line with the camper that i carry.
So my advice is to have a reputable spring shop do the work so it is correct and will pass dot if needed.
They are also going to add shocks to the rear
On the subject of lift blocks on big trucks. They are very common but are only used to level the truck and are available in 1" and 1.5". Also .5" is just a short leaf. Both of my class 8 trucks have them on the front axle.
Sent from my iPhone using Tapatalk Pro

Brilliant! Yet so obvious. May be the best answer so far.

"Take it to a suspension shop and let them do it, because they know what they are doing!"

They can provide you with documentation of the change in carrying capacity, which could effect registration and drivers license requirements.

 

[Buffalobwana]

Here is an idea. Follow me on this. And don't try to criticize the plan until you read the entire thing!

measure the amount of travel the springs give over the course of a 30 - 60 mile drive on-road. Determine how much flex happens in normal driving. Write that number down. (It can be done with some sort of retractable rod mounted in the proper position.)

Jack up the body of the truck. See how much the springs flex under normal load. Write that number down.

Now you know what the springs do sitting there how much flex they take just from weight of truck, and how much flex happens under driving circumstances.

Find some airbags that have more than that amount of travel AND are rated for that much weight, or more. Install said air bags, pump them up to take most (50-75%?) of the travel of the truck off the springs, let it be most of the FIRST bit of suspension travel. Then the hard as a rock springs take over after the bag gives enough.

The bags will be adjustable. If you want to off-road with it, air up or down, or whatever you want to do with it.

You do risk popping the bag, if you don't engineer it properly, but they are not too expensive to replace, and after all, this is an experiment by a collective mind of barnyard engineers (that is a compliment, by the way).

It will work. If it doesn't, it's my money I wasted.

Ok, now you can criticize it because I want to know your thoughts. If you think there is a soft spot in the plan.

 

[Mos68x]

I think it will depend on where you plan to place the airbags in relation to the axle mounting points on the lead pack as well as the leaf pack mounting points to the chassis. If I completely understand what you're thinking of, you're after a progressive style front suspension. I think it might be possible but will require quite a bit of work on the leaf shackles. if you only drive the truck on pavement with very little cross-country driving then I think this would be possible. I do a lot of cross country and raw land driving so for me I think the cab air ride would be better suited. Go ahead and chase that idea, I'm curious how you'd tackle it.

 

[someoldmoose]

bwana, just for accuracy my "degrees" are from the School of Hard Knocks with advanced studies at Redneck Community College and Creative Solutions Academy. C S A used to be called something else but it wasn't PC anymore so they hadda change the name. My sheepskin still bears the original moniker. Dean Riggins told me he was very proud of me.

As proof, I was discussing with our fleet mechanic the possibility of changing the front end to IFS ala' the Stryker / Oshkosh ARFF rigs. He used to work for Pierce (fire apparatus) and said the Tac 4 is a bolt on and the driven version is as well. Sooooooo, if I win the lottery or find an abandoned Stryker or Crash truck beside the road, and the prop shafts line up . . . . Hmmmm, hmmm, hmmmm.

That oughta ride pretty nice if our pumpers are any indication.

 

[profo]

I would like to chime in I put air bags on top of my leaf springs and I removed one spring so far and there is no noticeable difference my plan is to remove two more and stop at that if it doesn't improve I am working with a spring company to make a progressively load handling spring similar to a Lmtv spring the problem with my truck it is a camper and I can't haul a heavier load other than a trailer which is on the rear so it should be able tweak easily, I also found out that since I have a 8.3 it's a lil lighter than the 250 engine but I believe they both use the same spring, so with this said the springs are just to heavy for normal use around house, I put a camera under truck focused on spring and unless you jump a railroad track they DO NOT FLEX more that a 1/4 inch on normal LOUISANA roads!

 

[quickfarms]

Brilliant! Yet so obvious. May be the best answer so far.

"Take it to a suspension shop and let them do it, because they know what they are doing!"

They can provide you with documentation of the change in carrying capacity, which could effect registration and drivers license requirements.

I told them to configure the springs to carry the truck, 20,000 lbs with 12,000 lbs on the tandems, plus the camper at 5,000 lbs, plus the trailer tongue weight at 3,000 lbs and add 2,000 lbs for?

The 2,000 lbs will be partially used when I mount additional water and holding tanks.

As far as registration goes it is registered as a motor home so there is no change

 

[someoldmoose]

That just might be the best idea yet. The suspension installed was designed for a certain load. If you are never going to carry that weight then there is nothing wrong with having "lighter" springs installed. In fact, it's a very good idea. Just remember to have some kind of "tag", sticker, or revised data plate installed that indicates the "new" GVW, GCVW, and axle ratings. Not sure how other states are for truck tags but it MIGHT getcha a less expensive registration with a lighter GVW, and maybe even a lower insurance premium. Heavy things do more damage than lighter ones when they hit stuff.

OOPS, missed the part about registered as an RV. Gonna start mine as an Antique / Historic. Might change it to an RV when I'm ready to drive it more. Who knows what the future holds ?

 

[Buffalobwana]

I would like to chime in I put air bags on top of my leaf springs and I removed one spring so far and there is no noticeable difference my plan is to remove two more and stop at that if it doesn't improve I am working with a spring company to make a progressively load handling spring similar to a Lmtv spring the problem with my truck it is a camper and I can't haul a heavier load other than a trailer which is on the rear so it should be able tweak easily, I also found out that since I have a 8.3 it's a lil lighter than the 250 engine but I believe they both use the same spring, so with this said the springs are just to heavy for normal use around house, I put a camera under truck focused on spring and unless you jump a railroad track they DO NOT FLEX more that a 1/4 inch on normal LOUISANA roads!

which spring did you remove? If it was second from top, I would think it would make a bigger difference than second from bottom. Taking out every other spring starting at 2nd from top (remove 2 or 3) I think, should make a difference. If possible shortening the ones on bottom would make a difference too.

your idea about the LMTV springs was one I was thinking about. I loaded an LMTV trailer with 3 tons of cottonseed. It flexed. It definitely flexed under the load. But, it doesn't have the spring setup a 5 ton does.

Any way to get my hands on a set of front end springs reasonably? If so, start from bottom and remove every other spring, replacing it with the size smaller spring from the donor set. Or, try something like below.

So if the springs are numbered (from bottom to top, I am guessing 9 springs, just as an example, 9 is top spring 1 is bottom)

Normal configuration
9
8
7
6
5
4
3
2
1
New configuration remove #3 and #6 and add an additional #1 and #2 to the bottom to maintain height 9-7 is where your flex will happen removing #6 let's them flex more because they have less support under them. Under heavy loads, 4&5 can flex a bit more without the surface of #3 below them.

9
8
7
5
3
2
2
1
1

Your 1's and 2's are acting more like blocks now (they did before too) and 7-9 are doing the most flex.

Its all academic until someone tries it. We could debate it, but, results from actual tests don't lie. The question is, who will step up to the plate?

profo did already. Props to him. Profo, if you are going to remove more soon, please let us know how it went.

 

[Csm Davis]

I would like to chime in I put air bags on top of my leaf springs and I removed one spring so far and there is no noticeable difference my plan is to remove two more and stop at that if it doesn't improve I am working with a spring company to make a progressively load handling spring similar to a Lmtv spring the problem with my truck it is a camper and I can't haul a heavier load other than a trailer which is on the rear so it should be able tweak easily, I also found out that since I have a 8.3 it's a lil lighter than the 250 engine but I believe they both use the same spring, so with this said the springs are just to heavy for normal use around house, I put a camera under truck focused on spring and unless you jump a railroad track they DO NOT FLEX more that a 1/4 inch on normal LOUISANA roads!

Hey bud can you post a couple pictures of the spring setup you have.

Sent from my SM-G930V using Tapatalk

 

[simp5782]

The rears take a pretty good beating as well. This bogey was installed in December. Broken lower leaf on both sides. Heaviest bed cargo has been a hmmwv. Or tires.

Sent from my SM-G935P using Tapatalk

 

[Swamp Donkey]

Just add something useful to the front like a winch, heavy bumper or storage boxes...or all of the above. Replace shocks with some gas units and keep the shackle pins well greased. Make those springs work a little and you'll find comfort.

My front axle scales 12,700# as it sits in the picture. It's like driving a cloud. Even a couple hundred pounds will make a bigger difference than you think. I didn't add all that at once.



M939 with Tak4 suspension...

 

[Buffalobwana]

Both of those are the way forward for sure.

I am building a special custom front winch bumper for the 931A2 and two 923A2's. I like your bumper setup. Nice lines and a lot of 1/2"(?) steel. My design is a bit different, but may borrow some ideas off your truck if you don't mind.

 

[Floridianson]

The rears take a pretty good beating as well.

The way your trucks sits I would have to agree.

 

[quickfarms]

The rears take a pretty good beating as well. This bogey was installed in December. Broken lower leaf on both sides. Heaviest bed cargo has been a hmmwv. Or tires. View attachment 684223View attachment 684224

Sent from my SM-G935P using Tapatalk

It looks like your bottom leaf may be cracked from the photo.

Can you post a picture(a) of the entire spring and suspension

 

[simp5782]

It looks like your bottom leaf may be cracked from the photo.

Can you post a picture(a) of the entire spring and suspension

Yes one is broke and starting to walk out. One is just cracked. This is the second set of springs on two different bogeys.

I will post some pics tonight in my 60k mile report.

Sent from my SM-G935P using Tapatalk

 

[Mos68x]

I wonder how the rears will fair with 10k# on the rear full time time as an RV then. Makes me wonder about the longevity. Do you have any prior knowledge about that bogey before it was installed? I.E., miles and age? I really don't like the idea of having to change the design of the suspension for creature comfort, but I would if it were to avoid future breakdowns, especially with where I'll be going.

 

[Swamp Donkey]

Both of those are the way forward for sure.

I am building a special custom front winch bumper for the 931A2 and two 923A2's. I like your bumper setup. Nice lines and a lot of 1/2"(?) steel. My design is a bit different, but may borrow some ideas off your truck if you don't mind.

There's a good bit of 3/4" material in there too. Borrow all you want. I don't mind. Everything I've added up there serves a purpose. The secondary benefit happens to be a smoother ride.

My example is a bit extreme, as far as weight, but the point is that it doesn't take much of it before you start noticing a difference. A little weight up front has a large amount of leverage over the rest of the truck, given the distance to the trunnion. It'll also create a more balanced ride with a load in the back, or a box like some of ya'll are talking about.

Something else to consider on trucks that are not driven frequently is rust in between the leaves of the spring pack, whether light or rusted solid. Trucks driven regularly will have polished leaves and a smoother ride because of reduced friction. If you don't drive it on a regular basis then take it down a dirt road every now and then to keep those leaves polished. Or just head out of Macon on I-16. The whole truck will be polished, but you might not have any teeth left, lol.

 

[someoldmoose]

Pennsylvania's roads will leave my packs shining like the sun. And my kidneys even more damaged than they are now. Another old trick, if it'll be parked for a while, spray the packs with penetrating oil. Not a perfect solution but every little bit helps. Still haven't tried the ATF / acetone thing but this might be my chance.

 

[Swamp Donkey]

Lubricating spring packs is a quick way to break springs. They need some friction or they are easily overstressed when compressed. This is the same way spring leaves that are frozen due to rust are overstressed when they can't compress. Just keep them flexing and they'll be happy.

 

[someoldmoose]

Haven't had any break from being sprayed while parked. I am talking about sitting for a few months. Overloaded ? Yes. Rusted from sitting ? Yes. But never when maintained and loaded properly. Agree that use is the best solution.