Rear end noise during slow left u-turns

[flyboy618]

I have a '99 RT and it is making a grinding sound from the rear end only on sharp slow left turns. It does not make the sound at any other time. Could this be from the pressure applied on the rear wheel universal joint? Any advice out there?

 

[kcobean]

I would guess differential first. Has your diff fluid ever been changed/checked?

 

[AviP]

Not u-joint, but differential. I think the only way to check the differential is to take it off. If you want to eliminate the U-joint as a culprit, jack up the rear onto jackstands, chock the front wheels and run it in gear so that the rear wheels turn. Then go about searching for odd sounds. If it is bad differential in the early stages, you should not hear any abnormal sounds.

 

[PSilverGTS]

I would change the oil in the rear. It's only good for 12k miles or 18 months. I'm about to change mine. Don't forget the fiction modifier.

 

[SammyV]

Could be rear wheel bearings!(mine was!) Jack up the rear and grab the wheel and tire at 12 and 6 and see if you feel any play. Make sure it is out of gear and emergancy brake is off. SammyV

 

[kcobean]

I would change the oil in the rear. It's only good for 12k miles or 18 months. I'm about to change mine. Don't forget the fiction modifier.

Yes, you want to make sure you get at least a little truth in there.

 

[Joseph Dell]

could also be the tie rod ends. don't laugh.. a vca member had just that be the issue even though it sounded like rear-end noise.

 

[Mopar Steve]

Maybe too much dairy products, does it to me.

 

[kcobean]

Maybe too much dairy products, does it to me.

LOL...only when making slow left U-turns??? What kind of dairy are YOU eating?

 

[RAYSIR]

Seems to me the rear end posi plates would do the noise in either turn and its not a grind but a klunk and **** feel. Sounds to me like a brake pad, possible not releasing e brake all the way. U joint usually a clunk-clunk even in straight line. A wheel bearing if real bad because load thrown to one side.

 

[Vic]

Mine does that to. Will check for wheel bearings. Thought it might be the diff, but the hub carrier keeps the half shafts from poking into the diff, huh?

 

[Bill Pemberton Woodhouse]

Don't get too worried ,as many have suggested it could just be fluid. Heck, many times no friction modifier is even used for some folks racing , and then an old trick in the parking lot may alleviate the noise too. Go around in a circle about 10 times in one direction, then reverse and do 10 more the opposite way. You may find this makes the noise go away. I would not be surprised if just a fluid change, some friction modifier , and viola it is fine. If they have not tapped for a drain plug , give us a call, as that is a good idea ( unless you take it to someone who has never done it). Concerning when to change the fluid, 12,000 miles is not the magic number, as many Snakes will need a change as early as 5,000 miles ---- with all the torque Vipers have it often needs to be changed more often than suspected.

Those who run/ran Viper Days, will often change the rear end fluid after each weekend of racing. We have changed rear fluid at very low mileages at times and the smell from burned fluid would reek throughout the service bay. At this point your symptoms suggest nothing too major, but it would be wise to check it out , as most of the ideas given are possibilities.

Respectfully,
Bill Pemberton
Woodhouse Viper

 

[Vic]

Herr Pemberton,

Thanks for the tips!

I heard Woodhouse Ford in Nebraska, mentioned in a Galpin Ford radio commercial, out here in Southern California. Something about trying to beat Woodhouse for volume. I just thought it was funny to hear the name Woodhouse way out here in So Cal.

(simple things amaze me)

 

[flyboy618]

Yes, all of the rear fluids were changed just before VOI. I noticed it when we were on the second day at the track.

 

[Steve 00RT/10]

Like Bill Pemberton mentions above, Unitrax also recommends doing several figure 8's in a parking lot when breaking in their gears and getting the fluid moved around in there. It very well could be you just need a little friction modifier, but should probably change the whole works out for starters. With lube analysis, I've gone over 22,000 miles on my 3:45 rear end oil including track time. Came back good to go for more. The lower the gears, the more they turn, and heat becomes more of an issue given the differential case size is small to begin with.

Steve

 

[ViperRed]

Sounds like diff fluid low to me!