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ramman 01

thumping sound when going around corners at an idle

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hi guys i am fairly new to the site and i want to thank you all for the tons of imfo that is posted on this site . It's fun to read and learn how to fix any problems one may come across without having to pay the big buck to take the truck to a shop,so keep up the good work and thanks to Mopar Man for making this site available.Thanks again KevinOk now i have a problem.I can drive the truck all day with out any problem but if i pull into a parking lot or go through a drive through and have to stop an wait for the line up to move this is where it starts.As i let the my foot off of the brake and let the truck move forward at an idle it will make a thump and roll a bit and thump and so on and maybe even worse if i am turning but i can put my foot on the brake and put minimal pressure on the fuel pedal and keep going the same speed and it won't do it.thanks for any help

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My guess is a rust spot or other imperfection in a brake disc. When it's just slipping by it bumps it, when the pedal is fully released it does not.

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Do you hear the thump or feel it and if felt where is it felt at or through like felt the floor thump or felt the steering wheel thump ect. Will help me narrow it down for ya. After owning three 2nd gens I pretty much know what the culprits can be.:rolleyes: Crawl around underneath and check the obvious like u-joints ect, The trans shift linkage that is mounted to the cab to chassis has a shaft that needs grease every once in a while and it will cause a heck of a thump when its dry. You will feel this in the driver side floor board. The lower bushings in the steering column will cause a thump feeling in the steering wheel both will and are usually only noticeable as you describe while creeping along and about impossible to isolate. Also 2nd gen cab mounts have been known to break out of the bottom of the cabs if its ever been used and abused hard. I have never seen it but have heard of it many many times in my area but have never read it on any forum. I guess we are harder on them around here than anywhere else but the was a factory update repair for the issue so it does happen elswwhere I guess. Make sure the front shock mount bolts are tight, I have ran into this on every 2nd gen. they come loose and bang usually the lower bolt is the culprit it will seem tight but it moves up and down in the bolt hole on the axle and can be hard to see. look for fresh movement tracks in the rust ect of the bolt head area Or just cranck them down they can be tight but do not squeeze the shock hard enough and the shock is moving on the bolt causing a thump. I have seen it both ways. Most common is the track bar end is bad and loose where it connects to the frame. This will be noticed more when driving slow also and I would lean towards this being the culprit. Once you have checked all of these I will throw more at ya!:drool:

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hi, sorry i should have mentioned that i have replaced all four brake rotors ,pads, front wheelbearings and the u joints in the front axles and front drive shaft. I cant hear it but feel it and it seems to be mid to rear of truck and will only do it sometimes but only rolling at an idle with my foot off the brake pedal and what i mean about a rolling idle is when i come to complete stop and then like i said let my foot off the brake and just let the truck start rolling on its own if this helps any

--- Update to the previous post...

Do you hear the thump or feel it and if felt where is it felt at or through like felt the floor thump or felt the steering wheel thump ect. Will help me narrow it down for ya. After owning three 2nd gens I pretty much know what the culprits can be.:rolleyes:

Crawl around underneath and check the obvious like u-joints ect, The trans shift linkage that is mounted to the cab to chassis has a shaft that needs grease every once in a while and it will cause a heck of a thump when its dry. You will feel this in the driver side floor board. The lower bushings in the steering column will cause a thump feeling in the steering wheel both will and are usually only noticeable as you describe while creeping along and about impossible to isolate.

Also 2nd gen cab mounts have been known to break out of the bottom of the cabs if its ever been used and abused hard. I have never seen it but have heard of it many many times in my area but have never read it on any forum. I guess we are harder on them around here than anywhere else but the was a factory update repair for the issue so it does happen elswwhere I guess.

Make sure the front shock mount bolts are tight, I have ran into this on every 2nd gen. they come loose and bang usually the lower bolt is the culprit it will seem tight but it moves up and down in the bolt hole on the axle and can be hard to see. look for fresh movement tracks in the rust ect of the bolt head area Or just cranck them down they can be tight but do not squeeze the shock hard enough and the shock is moving on the bolt causing a thump. I have seen it both ways.

Most common is the track bar end is bad and loose where it connects to the frame. This will be noticed more when driving slow also and I would lean towards this being the culprit.

Once you have checked all of these I will throw more at ya!:drool:

hi Wild and Free , i think i have covered all that you mentioned but it almost seems that some thing is binding but its really wierd because if i give it just very little throtle it wont do it. Anything over 4 or 5 klms per hour it wont do it iether

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I would still check the other things first as thumps can be very tricky to know where they originate. The fuel tanks don't have a very good baffle system either and these rigs are known for fuel sloshing causing a wierd feeling also at low speed take offs. Make sure the spare tire mount cable is tight I have seen the cable come loose and the tire swings a bit and bangs around also. sounds dumb but it happens. Like I say check all the simple stuff first.

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Double check to make sure that the bolts to the calipers are tight, as well, make sure that the sleeves that the caliper bolts go thru are seated properly. Speaking from experience. :doh: What you describe is what happened to me. One of the caliper bolts had worked its self out (the sleeve was not seated properly) and was causing the symptoms you described. Make sure that you have the bolts lubed with grease as well.

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i remembered sometime ago a buddy saying something about it could be the clutch pak in the rear diff but i am not convinced of that as it i don't feel it at regular driving or like i said speeds or 5klm p/h

--- Update to the previous post...

Double check to make sure that the bolts to the calipers are tight, as well, make sure that the sleeves that the caliper bolts go thru are seated properly. Speaking from experience. :doh: What you describe is what happened to me. One of the caliper bolts had worked its self out (the sleeve was not seated properly) and was causing the symptoms you described. Make sure that you have the bolts lubed with grease as well.

thanks gassernomore i will check that on the weekend as i have'nt covered that one yet

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i remembered sometime ago a buddy saying something about it could be the clutch pak in the rear diff but i am not convinced of that as it i don't feel it at regular driving or like i said speeds or 5klm p/h

--- Update to the previous post...

thanks gassernomore i will check that on the weekend as i have'nt covered that one yet

Limited slip will usually chatter or ratchet, never seen one thump.

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the only way i can visualize it in my mind from sitting in the truck when i feel it is if you were to put a bean bag in a cement mixer when it gets to the top of the drum it falls to the bottom making a thud and then when it makes another half rotation the same thing again if this makes any sense

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best cement mixer I can think of associated with turning is the rear diff. so my thought is when did you last change your rear diff fluid, here is a thought for you if its burned up (just saying for the sake of a thought process you could have just done a change on it for all i know) then essentially you have large clumps of sludge getting tossed around mainly by the ring, as you round the corner the get pulled up and thud straight down again, under normal acceleration the centrifugal force is enough that they just get slung around and around, producing little noise at all.,

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best cement mixer I can think of associated with turning is the rear diff. so my thought is when did you last change your rear diff fluid, here is a thought for you if its burned up (just saying for the sake of a thought process you could have just done a change on it for all i know) then essentially you have large clumps of sludge getting tossed around mainly by the ring, as you round the corner the get pulled up and thud straight down again, under normal acceleration the centrifugal force is enough that they just get slung around and around, producing little noise at all.,

thanks ,maybe if i get the chance this weekend i was going to pull the wheels off and chech the rear calipers so if i have the time maybe i will pull diff cover as i never thought of that one.This is why i decided to post it on the forum to see what other ideas were out there that i did'nt cover.Oh ,i see that you have a glowshift fp gauge and was wondering how you like it because i was thinking of ordering one for myself.

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ya that's what i thought . not sure how he did'nt notice something before it got that bad.i know these are loud but he should have heard some major thumping going on

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