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I bought a 96 extended cab 2500 4x4 12v almost a year ago. Braking was smooth when I first got it. About 6 months ago it started getting a bad wobble/ bounce in the rear end while normal and moderate braking. If I brake really slow it doesn’t do it until I’m almost stoped. It almost feels like a pulsing sensation like the ABS is kicking in every time I brake. It has newer shocks, helper leaf springs and Air Lift air springs. It drives just fine over bumps so I know it’s not the suspension. I do know these trucks are notorious for axle wrap under acceleration, and I do feel that. However, the sensation I feel is far worst than the axle wrap I feel during acceleration. It’s not the front brakes, as I do not feel it in the brake peddle or steering wheel. I can feel and hear it coming from the rear end. Could it be that the drums need to be adjusted? Or am I getting axle wrap while braking? I just ordered Longhorn Fab traction bars. It has a leveling kit only with 33”x12.5 tires. There is no brake shoe noise while braking either. Everything sounds fine/ normal. Just not the bouncing vibration/ pulsating sensation I get. I should also note the it isn’t really there while driving 55 and braking. But as I slow down, the feeling kicks in and gets worst as I slow down. I’ll have the traction bars installed this weekend hopefully, and will update any changes after that. Just looking for advise on anything else I should do/ check. Thanks!
 

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If it does it when you apply the E-brake while moving (to isolate the rear from the front brakes) then it sounds like a drum issue. The front brakes receive most of the braking power first, so any rear brake feedback would be felt under more moderate braking.
 

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Indeed the front brakes are used the most. I didn’t think about the parking brake though. I’ll try that tomorrow.
 

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Yea I'd be looking at either machining or replacing the drums, sounds like they are warped.
 

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I had the same problem not too long ago. A piece of brake shoe had broken off and was binding the drum.

In what scenario is axle wrap "notorious"? Certainly not in normal street driving.
 

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If you do basically any power adders it gets out of control pretty fast. We've had 350hp trucks on our dyno that would axle-wrap so bad the overload springs would be hitting and deflecting against the front frame pads. You don't normally feel it when it happens on acceleration, but I bet a GoPro camera would show quite a bit of movement in an "around town" sort of driving scenario at stock power.

When my truck was a manual with a dual-disc ceramic clutch, the grabbiness of the clutch would cause so much axle-wrap the overload springs would bounce off the frame pads. Shook the entire truck on takeoff and sometimes during normal shifts if I didn't finesse it just right. Towing made that worse.
 

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Discussion Starter #7
All factory leaf spring trucks have axle wrap. You just don’t notice it much on factory trucks, especially the older trucks with less power. But my 96 is over 400hp. So it bounces a little during acceleration, mostly in 2nd gear, even on a slow take off. The sensation I get during braking is the same as the acceleration axle wrap. but amplified way more. When I install the traction bars, I plan to open the rear drums and check them out.
 

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Check for Broken / Rusted thru springs and esp the rear shackle spring hanger . Seen a few of those broken / rusted badly . Also check the rubber in the spring eye.


My sons 12 v 5 speed with 3" lift , 4k governor springs , delivery valves waaay big and all the usuall kid tricks has HORRIBLE rear spring wrap. Even with me ( old man ) driving it "normal".
 

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I don't doubt there could be axle wrap in some circumstances. I am questioning the use of "notorious", i. e. famous or well known. I'm not aware of it in my truck and other than the drag racers it is never mentioned in the forums I subscribe to. An example of "notorious" is 2nd gen Dodge 4X4's "death wobble".
 

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Discussion Starter #10
I don't doubt there could be axle wrap in some circumstances. I am questioning the use of "notorious", i. e. famous or well known. I'm not aware of it in my truck and other than the drag racers it is never mentioned in the forums I subscribe to. An example of "notorious" is 2nd gen Dodge 4X4's "death wobble".

Check out YouTube. BD Diesel has a great video explaining axle wrap in a 4th gen. All leaf spring trucks have it. It just doesn’t cause most people concern, because most trucks are stock. But when you add engine power, it amplifies it. Sorry if my wording confused you. It is a well known fact, but it’s not as big of a deal to most people, especially when compared to the death wobble.
 

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Discussion Starter #11
Check for Broken / Rusted thru springs and esp the rear shackle spring hanger . Seen a few of those broken / rusted badly . Also check the rubber in the spring eye.


My sons 12 v 5 speed with 3" lift , 4k governor springs , delivery valves waaay big and all the usuall kid tricks has HORRIBLE rear spring wrap. Even with me ( old man ) driving it "normal".

All the springs and hangers are a great shape, and have no rust. The entire chassis is virtually rust free. I’m lucky there.
 

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If it does it when you apply the E-brake while moving (to isolate the rear from the front brakes) then it sounds like a drum issue. The front brakes receive most of the braking power first, so any rear brake feedback would be felt under more moderate braking.
So I applied the parking brake slowly while coming to a stop 3 different times today. It’s definitely coming from the drums. There’s no concerning noises coming from the drums. So I’m thinking the drums are just warped. I guess it’s possible, I just hadn’t heard of drums warping seeing how most of the stopping power comes from the front. I just thought maybe I was experiencing axle wrap while braking. That’s why I wrote the first message, to see if anyone has experienced it. The traction bars are being delivered today, so this will fix that issue. But I’m willing to bet the drums are warped. So I’ll work on getting the parts and fixing that in the next week or 2.
 

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Check for Broken / Rusted thru springs and esp the rear shackle spring hanger . Seen a few of those broken / rusted badly . Also check the rubber in the spring eye.


My sons 12 v 5 speed with 3" lift , 4k governor springs , delivery valves waaay big and all the usuall kid tricks has HORRIBLE rear spring wrap. Even with me ( old man ) driving it "normal".
Key factor: 3" lift. 4x4 trucks already have a lift spacer that the 2 W/D trucks don't, add a 3" lift and you worsen things. The leverage angles change dramatically as the axle centerline gets farther from the leaf spring.
 

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Discussion Starter #14
Alright y’all, here’s the answer to my problems. I’ll start with describing my truck more. And sorry, it’s long, but I wanted to do a good write up and review.

96 2500 12v 5sp 4x4 extended cab long bed. Bosch 350 Marine 40hp injectors, HX40 turbo, ARP head studs, 60lb valve springs with 4K gov springs, DevilsOwn water menthol injection (used to cool egt’s when towing up grades) ATS 3 piece exhaust manifold, BD Diesel blow off valve, Mishimoto intercooler and thermostat, Fleece coolant bypass, 4” down pipe to 5” Jamo Performance straight pipe with a Caterpillar 4” exhaust brake mounted between the down pipe and 5” exhaust, AFE intake, Redhead steering box, BD Diesel adjustable trac bar, Synergy tie rod bar, XDP gear reduction starter, South Bend clutch and a Gear Vendors under/ overdrive, rear axle has an add-a-leaf spring kit and Air Lift air springs with on board air. Leveling kit with 33x12.5 Cooper Discover AT3 XLT’s. There’s more I’m missing I’m sure, but you get the gist.

So back to the problem. I had the NV4500 and Gear Vendors rebuilt and the South Bend added less than 4K miles ago. The old clutch was bad and needed replacement. I had mild to moderate slippage and chattered a lot while switching gears. So after all that, with the rebuilt trans and new clutch when I’d accelerate in 2nd, the initial clutch engagement would chatter a little like the clutch was slipping. And it’d do the same in reverse. I was wondering why it was doing that until I researched traction bars and learned about axle wrap. During all this, over the past year, I had a bad chatter/ bounce while braking. At first I thought it was warped rotors. But then I realized it was coming from the rear end. So I was thinking either warped drums, or I was experiencing axle wrap while braking. I inspected the rear suspension and everything appeared good. My truck’s body and chassis is virtually rust free.

I tried researching axle wrap while braking, however I couldn’t find anything. I originally wrote this post to see if anyone had any input or similar experience. Today, 3/28/20, I spend about 3 hours of COVID-19 isolation outside installing Longhorn Fab Shop bolt on traction bars. Went for a test drive and holy molly what a difference!! No more axle wrap. No more acceleration chatter, no more reverse chatter, and best all, No More Brake Chatter!! So now I don’t have to do a brake job!! My truck accelerates and brakes smooth now! And I feel a good difference in the overall driving and handling of the truck. Wow I wish I would have got these a long time ago!

Thanks for everyone’s input. I hope this helps someone else. I can’t wait to tow my 35’ fifth wheel toy hauler and see how it tows!
 

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All I can say is there must be something seriously wrong with the springs if the traction bars eliminated what you call brake chatter.
 

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I had an issue with another truck few years ago where I was thinking I had a bad u-joint (this was in a dana 80 equipped DRW truck). As it turned out the leaf spring u-bolt nuts were a little loose (truck was, and still is, factory height, the u-bolts had never been touched outside the factory to my knowledge).

I tightened the nuts down as tight as I could muster with a 1/2 breaker bar, getting about one full turn on each of them, afterward the weird u-joint binding/ shaking feeling went away.

Maybe the installation of the traction bars fixed the problem because it eliminated the axle wrap caused by loose fasteners???
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I had an issue with another truck few years ago where I was thinking I had a bad u-joint (this was in a dana 80 equipped DRW truck). As it turned out the leaf spring u-bolt nuts were a little loose (truck was, and still is, factory height, the u-bolts had never been touched outside the factory to my knowledge).

I tightened the nuts down as tight as I could muster with a 1/2 breaker bar, getting about one full turn on each of them, afterward the weird u-joint binding/ shaking feeling went away.

Maybe the installation of the traction bars fixed the problem because it eliminated the axle wrap caused by loose fasteners???
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Not a bad idea , and free . Ill give this a try on the ole'94 5 speed , cant hurt !

thanks
 

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I had an issue with another truck few years ago where I was thinking I had a bad u-joint (this was in a dana 80 equipped DRW truck). As it turned out the leaf spring u-bolt nuts were a little loose (truck was, and still is, factory height, the u-bolts had never been touched outside the factory to my knowledge).

I tightened the nuts down as tight as I could muster with a 1/2 breaker bar, getting about one full turn on each of them, afterward the weird u-joint binding/ shaking feeling went away.

Maybe the installation of the traction bars fixed the problem because it eliminated the axle wrap caused by loose fasteners???
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Not a bad idea , and free . Ill give this a try on the ole'94 5 speed , cant hurt !

thanks
 

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Not a bad idea , and free . Ill give this a try on the ole'94 5 speed , cant hurt !

thanks
Maybe free for you. It cost me replacing two u-joints, and the carrier bearing, getting all four back tires balanced twice, and buying a set of centramatic wheel balancers (which the centramatic wheel balancers are great by the way , no regrets there) before I figured it out. So not really free for me, but I guess that's the cost of improper troubleshooting.
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Discussion Starter #20
I didn’t find anything wrong with my rear suspension. And all the u-bolt nuts were tight when I removed them to install the traction bar brackets. Hard to say for sure. I do know that with all research I did on traction bars, there’s a list of components that wear out prematurely due to axle wrap. Even if you don’t feel it in you’re truck, it’s doing it still. So it can cause suspension damage. Bolts to loosen, carrier bearings and u-joints to wear out, and diff gear damage. All I can say is it appears to have fixed everything.
 
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