2nd Gen Non-Engine/Transmission axle hop in snow

[xpetecx]

how do you get rid of it or just control it a little? If i dont do anything about it im gonna loose all the teeth in my head and the drive shafts under my truck.

 

[TRAMPLINEMAN]

Try using sand bags.

 

[Hohn]

You'll notice that the axle hop only occurs when you have a little traction.



With no traction, there's no axle hop.



One of the best things you can do to control axle hop is install high-damping rear shocks. In other words-- stiffer. The factory shocks (most aftermarket one, too) are too soft to control the monstrously stiff springs the factory installs.



Notice that your rear shocks are staggered, one is in front of the axle and one is behind. This allows the shocks to better control axle wrap.



For others viewing this thread, here's what causes axle wrap:



When you accelerate, your tires "push" against the road. But the road pushes back (physics), so it creates a twisting force in the axle. Basically, as the wheel "twists" one way on the axle, it makes the axle want to twist the opposite direction.



Your leaf springs absorb this twisting force and deflect into an "S" shape. Once you stop accelerating, the twisting force of the wheels is gone, and the springs release the stored energy and the axle starts jumping up and down. Then the process repeats itself.



The staggered shock design used on our trucks means that the shocks are positioned to help with axle wrap, because their damping motion opposes the twisting of the axle.



But the vast majority of shocks are just too soft, ESPECIALLY in rebound damping.



Upgrading the rears to shocks with more damping will go a long way towards helping with your rear axle wrap, without the need for more radical steps like custom springs that eliminate the lift blocks.



jh

 

[xpetecx]

I hate lift blocks. ok now that Ive got that out of the way, I'll pretty much use any reason I can find to get ride of the lift blocks. does anyone know of a spring that will eliminate the lift blocks with out lifting the truck?



So for now more weight and stiffer shocks. Ill try that. thanks for the help.

 

[HEMI®Dart]

Poor Mans Traction Bars..

I found that Roadmaster springs reduce axle hop by about 80%.



http://www.mrbobsdistributing.com/activesusp.html

 

[Hammer]

A good set of aftermarket ladder bars are another choice to eliminate the axle wrap issues you are having. There are a couple of good companies who make them and they have been listed in other posts here. If you do a search on them you will find what you seek. The long lift blocks in the rear are what causes the suspension wrap and "hopping" sensation you are experiencing. Good shocks will help to some point but will not eliminate it... ... ... . Andy

 

[xpetecx]

Hammer after looking at your rig I think im gonna make a set of bars like you got. Did you make them or buy them. they look realy good. I think thats the way I want to go.

 

[NIsaacs]

xpetecx, which truck are you talking about? The 4x2 or 4x4? If it's the 4x4, it is most likely only when in 4x4. The front coil springs are bad about that. In 1967 when Ford went to coils on the front of their half ton 4x4's the hop started. The older leaf spring fronts and the 3/4 ton leaf spring fronts didn't hop. If it is the 4x4, does it hop in two wheel drive? I am guessing the front is the guilty party, and no I don't know how to stop it





"NICK"

 

[Hammer]

xpetecx. .

My bars were built by one of our members,Darryl Poole,and sold by a member who has been banned for unscrupulous business tactics. However,there is a TDR member who is in Michigan who does make them and will make sure you get the product you desire. They are the same design and mount like mine are and can be powder coated about any color you desire. Drop a PM to LSFarm(Greg Long,owner of Great Lakes Diesel Works) and I am certain he can fix you right up.



If you desire a different approach foryour bar choice then here are a couple of other ideas for you then.



http://www.ntwonline.com/ (Fabritech Ladder Bars)

http://www.calvertracing.com/ (Cal Tracs)



I have seen either brand bolted up to our trucks at shows I have been too. Fabritech has two styles and can be seen on many TDR trucks. The Calvert Racing "Cal Tracs" are very well known around the NHRA/IHRA Stock and Top Stock Eliminator classes and are used by most ALL of the fastest stockers in the country because they flat out work. Hope this helps you some. If you decide on a set of LSFarms bars let Greg know I sent you there... ... ... Andy

 

[drrhoades]

With the Cal Trac bars would they bind when the truck was loaded. I. E. if the bed was loaded with couple thousand pounds. If they did bind would it hurt anything or is a common problem with all ladder bars.



Thanks,

Doug

 

[Hohn]

All ladder bars could pose a binding issue, depending on suspension travel, bar length, and such.

They can be made to work, but there are certain compromises that have to be worked around. Some of the compromises are non-issues for most guys trucks.

jh

 

[xpetecx]

Thanks for all the help Hammer. If I go with the Lsfarms bars I will let Greg know you sent me.

 

[drrhoades]

I am assuming that the longer the bar the more suspension travel you can have?

 

[DWeiler]

Greg is a honest man to deal with,my custom powdercoated bars(intense blue) are on the way as we speak(type :-laf ). He sent them last week even before the funds had arrived. ,it took a while to get them built and coated,he takes his time cause he is a commercial pilot,little room for error and is usually gone for a fair amount of days in a row. Since he takes his time that means to me they are done right and you get what you pay for---guality,i have never heard of any negative comments about his stuff---,my 2 cents.

 

[Hohn]

I am assuming that the longer the bar the more suspension travel you can have?

Not necessarily.



Everything that connects to the axle has to have its motion considered in the full range.



For example, the driveshaft has to have a slip yoke or the suspension would bind badly. This is because of the angle of the driveshaft and the fac that the axle is trying to move straight up and down.



The problem with leaf springs is that they do TWO functions. They serve both as the spring, AND as the suspension link.



This is different than a four-link setup, for example, where the function of springing the axle and locating it are separated.



The leaf spring is pretty much the worst overall suspension design, but it's cheap and works. With the live axle leaf spring, the suspension wants to move straight up and down.



But the drive shaft want to force the axle into an arc-shaped motion. Without a slip yoke, this would cause binding.







A ladder bar setup has the same considerations. Since the bar will attach to the frame somewhere and to the axle at some other place, it will NOT allow the axle to travel in a perfectly straight line up and down. in theory, an infinitely long bar would eliminate this (because the axle has a finite range of motion up and down) in much the same way that an integral in calculus is an approximation.



The ultimate setup would be a four-link setup where the locating links were perfectly parallel to the driveshaft throughout the range of travel. This would mean that the locating links and the driveshaft would exactly follow the same arc of travel, and you'd never have bind due to these components.



In fact, such a setup would allow more travel than a typical U-joint can handle.



jh

 

[plongson]

This whole idea about wheel hop, and axel rap etc has got me thinking...



I have a problem that is not related to snow and slippage but to towing at max capacity. When loaded up with the TT, bikes and all gear I tip the scale at around 18k GVCW. When conditions are right and I can get the boost up to around 30 psi and the egt is in check, I get a horrible bumping, jerking lurch, whatever you want to call it until I back off just a tad. I at first thought it was the clutch slipping... gave me a good excuse to get a NV5600 and a SBC (see my sig) It is not the clutch. It almost feels like a gasser missing under load... but the mighty CTD is not missing, in fact it seems to be pulling its heart out.



This brings me to the wheel hop/spring wrap theory. What about spring wrap on hard pavement, maxxed out in 6th about 70+ MPH??? Has anyone else felt something like this?? What do you think??



I was thinking about putting it on a dyno and loading her up to see if I could see this spring wrap...

 

[McCRam]

Mine does the same thing towing. The whole rear end will start hopping. New springs and ladder bars are in my future. This truck is intolerable in snow like the original posters truck. I am even thinking about using some 3500 springs.

 

[Rman]

This whole idea about wheel hop, and axel rap etc has got me thinking...



I have a problem that is not related to snow and slippage but to towing at max capacity. When loaded up with the TT, bikes and all gear I tip the scale at around 18k GVCW. When conditions are right and I can get the boost up to around 30 psi and the egt is in check, I get a horrible bumping, jerking lurch, whatever you want to call it until I back off just a tad. I at first thought it was the clutch slipping... gave me a good excuse to get a NV5600 and a SBC (see my sig) It is not the clutch. It almost feels like a gasser missing under load... but the mighty CTD is not missing, in fact it seems to be pulling its heart out.



This brings me to the wheel hop/spring wrap theory. What about spring wrap on hard pavement, maxxed out in 6th about 70+ MPH??? Has anyone else felt something like this?? What do you think??



I was thinking about putting it on a dyno and loading her up to see if I could see this spring wrap...

I haul gravel with my truck, short distances at very high capacities. I won't even go into GCVW, cause I'm WAY over it, by a large margin. It's not far though and I don't use busy roads. Anyways I experience this axle wrapping in a severe way.



When you have that much weight behind you and you want to start moving it, imagine what is trying to happen. The wheels start to turn, but the weight is preventing any movement, well the springs and shocks allow the axle to turn, and when you clutch or lose traction the springs release that stored energy and you start to hop. There's no real way to totally eliminate it. The above stated stuff will certainly help, but short of immobilizing the axle to the frame, it's always going to be a factor.



The best way I've found is just try smoothing out the acceleration. Take longer to shift to allow the axle to level itself. When you start grabbing gears and hammerin the throttle that's a recipe for disaster.



I experience this with only HEAVY loads. I've put 15 ton of gravel in a trailer that probably weighs about 8-9k pounds. Where's all those geniuses that think 3. 54's are so great, I'd kill for 4. 10's now... biggest mistake I ever made.

 

[BarryG]

PLongson:

After I got my auto transmission rebuilt I started experiencing that problem as well. Be doing 60mph or so and then get on it and oh boy not good. BAck off and all is well. Just had to acclerate slower. It only did it for me when I was towing. I noticed it on the way home from my transmission rebuild. I called the rebuilder and he immediately knew what the problem was. He said yeah we see that sometimes with the longbed trucks with the 2 piece driveshafts. He recommended lowering my center carrier bearing about 1/2 an inch. He said he has had to lower them up to an inch but most were fixed with 1/2 inch. I did that and sure enough it went away. I have since added some of lsfarm's bars and those also would fix it as well as really helped my wheel hop in the soft stuff.

 

[Rman]

wow, so lowering the carrier will help with wheel hop? I may have to look into that. Isn't there a member here that fabs a bar set? Isn't it Rob Thomas?