Duramax - Four-Links or Ladders

[More Power]

Still a ways out, but I've been thinking about how best to prevent spring wrap.

I've been clipping magazine photos and ads for months, but I'm still not sure what will work best for this truck.

The rear diff will be a 9-1/2" GM semi-floater equipped with a Detroit Locker and six-lug wheels & 31" tires. The torque limit of this axle is close to where we'll be running, but 4x4 experts knowledgeable in such things say traction will likely give up before the ring/pinion do.

So, does anyone recommend any traction aids, or can you point me to some examples of rear suspension buildup that would work for this truck?

Thanks,

MP

[ 01-04-2004, 06:42 PM: Message edited by: More Power ]

[Dieselboy]

I'm a big fan of leaf springs. They're simple, and controlling wrap isn't that hard. Ladder bars are a cost effective way to have good road manners and suspension travel without radical warping of the springs at the quarter mile track. If you know a guy that can fabricate pretty well, build a custom setup.

I would steer clear of a four link right now. You'll spend nearly as much time mocking up the rear suspension as figuring out how to adapt the engine and tranny. They're cool, and you can always switch later after you give a try at leaf springs.

BTW: great forum!

[gene smith]

MP
If you are not going to be hauling in the back of the truck and doing a lot of street and some raceing i Highly recomend the 4 link set up with coil over shocks. I ran this set up an it can be adjusted for street or strip very easy. Summit Racing or Jegs Performance has the complete kits for any diff housing. Good luck
Geno

[More Power]

I don't know what the future holds for this truck, beyond a couple years of doing duty as a test bed for ideas and products, and outrunning Dodges.

Right now, I'm inclined to use ladders, simply because the suspension could be kept more or less intact. However, if the demands of the track require it, I'll go the four-link route.

How are the fastest GM's & Dodges coping with spring-wrap?

MP

[Kennedy]

I got the idea for my mud truck's torque link from an off roader. We welded a large stud pin to the top of the rear diff housing, and ran a single link more or less paralell to the driveshaft. Simple, light, effective and never failed. You can adjust the pimion angle with caster shims between the springs and axle...

[BETA]

I think you should try "How to make your car handle" by Fred Puhn. It's a bit old, but I'm sure you will find it very informative.

[More Power]

Thanks Christer...

I ordered a copy...

MP

[gmctd]

I'll have to hang with JK on this one - an adjustable end-link allows easy pre-loading for various road\track conditions, and easy disconnect.
A simple pair of rectangular tubing bars with rubber snubber\bumpers, bolted to the axle at the spring plates, can control spring arch at high-power launches while not interfering with normal ride.

If the truck will be all wheel drive, may not need the lower bars, but the upper link is an easy modification.

[ 01-13-2004, 08:28 AM: Message edited by: gmctd ]

[mhagie]

A little spring wrap isn't all a bad thing, In 1964 I had 64 plymouth Fury with a street 426 wedge with the t/flite pushbutton automatic.
I could run it up against the brake slide foot of brake and nail it, tires would just chirp a tad and car would basicly leap from the line cause a bunch of the torque was absorbed by the springs.
In order to maintain the impression of cool I installed a set of traction masters between axle and front spring eyes,looked really cool but that was the end of my good launches, with the t/masters not allowing any spring wrap the car would instantly go up in smoke w/both rear tires.
Of course that is no comparison to you d/max guys
you probably have more torque that my old mopar ever thought of.
The good thing aboult the old girl was spring wrap and all it never did the bouncy bounce thing like the POS Fords did, I saw more than one of them spit the driveshaft and tranny tail housing out on the strip. LOVED IT :D ...Merle