The clunk thing

Ok, ive read most of the clunk catagorys but I dont think ive found any answers. I was having a clunking problem before when id make sharp turns. I shifted the transfer case to 4 low and pulled the E brake as hard as posible. I had someone get in my VX and told him to shift from foward to reverse. Holy crap, the front diff moved about 3 to 4 inches on the mounts, thats not rite at all. I pulled the front diff to check the mounts and they were fine, a buddy of mine told me to make some urathane shims because the mounts might be week from age, abuse and that fixed the problem. It worked well till about a month ago. Now when I lay on the brakes to make a stop then let off the brakes I feel and hear a major clunk and its not gear lash. It sounds like a major shift of a componant. I cant get it to act up on a lift either and I checked that all the bolts were tight. Im about to rebuild my transfer case bacause of leaking seals. Anyone think it could be that the chain in the transfercase has been over stretched or is there any other ideas. The truck runs strait and feels very tight and smooth considering the abuse ive put it through. It used to start shaking a little at 75 but after the shims were inplace it drives smooth as silk to 100 plus. I wish I would have done that before I drove crosscountry. Ive noticed alot of the same style mounts on alot of the moving suspension parts and im thinking of shimming them all.

my VX has always done that clunk after very hard braking, just figured it was normal. i prepare for it now, when i come to a hard stop i just shift to neutral for a second to relieve the tension

My VX would clunk if I didn't come to a complete stop and then hit the gas. The transmission had a slight leak and it was slipping. Maybe that's what is going on?

Na, tranny is tits. Ive checked the fluid when I changed, no band crap.

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Originally Posted by etlsport

my VX has always done that clunk after very hard braking, just figured it was normal. i prepare for it now, when i come to a hard stop i just shift to neutral for a second to relieve the tension

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Im pretty sure its not normal, atleast on mine. Im woundering if it has to do with the rubber mounts in the A arms. Maybe you load them under hard braking and when you release them they become unsprung causing the clunk. Another thought is like I said before about the transfercase chain having slack. There does seem to be alot of backlash in the drive shaft entering the transfercase. If the rebuild for the transfer case costs 1100 in part, I wounder how much it would cost to put fresh gears, bearings and seals in the front and rear diff, couldnt be that bad. Im trying to keep this truck alive for atleast another 100,000 miles if not more.

not sure what could be cuasing it but its a similar feeling to when i start the vx and put it into drive while the e-brake is still pulled. the vx doesnt actually move but it feels like its raising

"not sure what could be cuasing it but its a similar feeling to when i start the vx and put it into drive while the e-brake is still pulled. the vx doesnt actually move but it feels like its raising"

That's axel wrap & it's normal.

i was going to ask about the clunk too. when im in low and shifting between drive and reverse there is a cluck and jerk. i twisted the drive shaft by hand and there is about a quarter inch of play, so i assume the clunk is the drive shaft twisting free before catching and that low range amplifies the jerk by applying more force( torque ). i was thinking worn u joints, but could you explain axle wrap as this may be the problem.

Well i too have the sprung energy thing after releasing the brakes and i have thought it might b the brake callipers,my callipers although securely bolted on have a small amount of play in them when grabbing them and jerking front to back so i thought they might be being drivin forward when braking to a stop and then when the brake is released they spring back, idunno just a thought.

I guess I used the term axel wrap too generally. When your vehicle 'stands up' with the parking brake applied, the same forces are at work, just not to the same extent.

"Wrap-up - Referred to as both rear spring and rear axle wrap-up. As power is applied, torque load causes the rear pinion to pivot upward. Once this load reaches a certain point the leaf springs begin to deform, which stresses numerous driveline components. The "fix" is to increase spring strength, via add-a-leafs, or install traction bars."

I know that this definition is for leaf springs but similar effects will be in play with coil springs. Remember when Kicker shocks, sub frames & ladder bars were the 'all the rage' with agressively lifted trucks? Those were all cures for axel wrap (wheel hop) just like steering stabalizers were supposed to stop 'bump steer'.

There is a TSB that says the clunking is normal.. Mine has clunked since it was brand new

Well, theres all kinds of stuff that can clunk. Its the how bad is it or is it getting worse that you need to keep an eye on. If you run the the VX hard, things are going to wear alot quicker. I think im going to start buy making more of the shims I mentioned before and do part buy part while testing in between. Im still waiting for the clutch pack wich is on back order from isuzu. Id recomend that the guys that own one and plan on keeping it on the road withought a long wait start collecting parts. Were lucky that the tranny parts are readily available since its a common tranny but what about diff parts. Has anyone looked into diff parts? I havent had the time to pull any schematics yet.

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Originally Posted by MoonRaker

Well, theres all kinds of stuff that can clunk. Its the how bad is it or is it getting worse that you need to keep an eye on. If you run the the VX hard, things are going to wear alot quicker. I think im going to start buy making more of the shims I mentioned before and do part buy part while testing in between. Im still waiting for the clutch pack wich is on back order from isuzu. Id recomend that the guys that own one and plan on keeping it on the road withought a long wait start collecting parts. Were lucky that the tranny parts are readily available since its a common tranny but what about diff parts. Has anyone looked into diff parts? I havent had the time to pull any schematics yet.

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For the rear diff., I just ordered...

L & R bearings, a complete set of shims, & 12 ea. ring gear bolts.

All ordered from Merlin, we also talked about pinion bearings, shims, seals, & crush collar.
There was no mention of any of these items being on back order, but I won't know for sure until they do, or don't, show up next week. :_wrench:

All the seals and bearings shouldnt be hard to find what im worried about is all the gears to include the pinion. Ask if there available if you dont mind.

Sorry Moon, but my order is in & I don't have time to be your secretary...

1-800-727-8066 St. Charles Isuzu - ask for Merlin!:smilewink