Mattysals

Hello all, I have an 07 base with the oem differential. After driving for about 2 hours back home after an exhaust change, I noticed a weird clunking/scraping sound coming from the center/rear area. It is especially noticeable when letting of the gas and letting the car slow down. No gears were missed or anything like that, and the car drives smooth besides the clunking. It's never done this before, does anybody have any ideas or suggestions as to what this may be?

kno

iTrader: (22)

Ill sell you my pumpkin with vlsd 3.3 gearing I had on my base for 80 bucks you pay shipping. Its a steal but its an extra part I have collecting dust in my garage

Mattysals

Once I find out what the definite problem is, I'll let you know. If it is the differential I will tak you up on that

Mattysals

Anybody?

jv350z

iTrader: (6)

is your diff bushing blown?

Mattysals

Not sure, I really don't know much about differentials. Where and what am I looking for with the bushing

Daytondakid13

Same happened to mine and cannot figure out the problem but it only happens on deceleration or when I get off the gas

jv350z

iTrader: (6)

Go behind your car, get on the ground and look at the diff (cover). See any black goo splashed/running on the cover?..if so, it's blown. Not sure if this would cause what you're experiencing, but I do know that a blown diff bushing allows the diff some movement.

Also, I've been reading the FSM because I'm about to upgrade my diff and found this.

RFD.pdf.pdf

Again, not sure if this is what you're experiencing, but it's something to keep in mind.

Mattysals

Thanks, once it stops raining ill take anlook

jv350z

iTrader: (6)

You also mentioned that you just got some exhaust work done, so I guess you need to check that everything is properly tied down. Maybe your sway bar is banging against your exhaust.

Mattysals

I double checked every bolt before I was done but I guess it won't hurt to check again

Mattysals

Alright so an update:

This noise does not happen upon starting the car and driving, I just drove and it didn't start until about 3 miles in. It almost sounds like an exhaust break when I let off of the gas, but I know it is not the exhaust. It's a clunky sound, once it stops it does not go away. If i let the car sit at an idle after driving, you can hear it and then it fades away.

Does anybody have any idea? This is really starting to get to me. I've had nothing but problems with this car since I had it. I've done all the proper things to keep the car well maintained. After one problem is fixed, in comes another. Please any help would be appreciated.

Daytondakid13

What it is I found the problem with my car and another car. I thought it was the differential and it is but nothing is worh with it. What it is is that the diff bushings are allowing the diff to move which if you have an after market exhaust it will move and the axel flange will hit the exhaust, which it will be spinning into. Therefore making the loud noise your hearing so you can either tighten the bolts that hold the differential in place by the bushings or get new bushings and install them and reinstall the diff

Mattysals

That sounds logical, but if this is the case why would it only happen upon slowing down and not start up? Do you have any pictures you can post so I can see what in looking for

Daytondakid13

Slowing down causes the differential flange to drop lower since there is no power being applied to the diff. I went under the car and put the car on rear jacks and saw it happening. The differential flange is falling a few mm which is causing it to spin lower which is creating contact with you exhaust. The diff pumpkin has 4 flange bolts up front connecting to the drive shaft and then 2 holding the diff steady on both sides know as the ears. Those two bolts should be tightened and maybe take out the two metal parts on top of it to give the diff an extra 2-5 mm of clearance.

Mattysals

Which exhaust do you have?