Rear end noise..

[pablo_max]

Hello,

I purchased my first 280z (83 non turbo) some months back for a couple hundred bucks. It had sat for 2 years and didnt run at all.

After a new ECU, injectors and some various wiring, it back to running condition. I replaced the tires and struts as well.

The problem I have not seen the cause of is a rear end noise. It is a loud clank like something smacking into something else. This only happens on a strong down shift or when starting in 1st gear I run close to the line and press the clutch. When the drive disengages it clanks. It sounds for sure to be coming from the back like someone is kicking in the butt.

Any idea? I thought perhaps the u-joint, but i greased them up and they all seemed nice and tight. Maybe the differential mounts?

Any ideas on the most probable place to start would help me out.

Many thanks. Patrick

[evildky]

280ZX

sounds like either the diffpinion mount or the trans mount, these deteriorate with time and fluids leaking on them, get the car up on jack stands and try prying up on the pinion mount and the trans, if you get any measurable amount of movement you have a bad mount

[pablo_max]

Thanks for the reply. Are these difficult to replace?

[NSR_s30]

Yikes sounds kind of serious. From what you described I thought it was maybe bad ujoints...

[evildky]

no not hard at all, the trans mount just requires you support the trans while you pull the crossmember and replace the mount, the pinior mount doesn't really require you support the pinion but if you put jack stands under the inside tube on the laca's it holds them in place while you pull the crossmember, the bolts that go through the front of the diff can be a pita but not really a big deal, honestly it's easier than dealing wth a u-joint as the u-jointts are not servicable and would have to be replaced at a driveshaft shop

[NSR_s30]

Yeah even if they're the servicable ujoints, you're always better off replacing them.

[evildky]

i mean they are nto servicable in taht you can't pull them out with retainers like in domestic's, you have to have the retainer tabs ground out then press the housings out, huge pita, and then when you replace them becasue after removing them there si no re-using them, you have to press the new ones in and steak them

[NSR_s30]

i mean they are nto servicable in taht you can't pull them out with retainers like in domestic's, you have to have the retainer tabs ground out then press the housings out, huge pita, and then when you replace them becasue after removing them there si no re-using them, you have to press the new ones in and steak them

I just replace them instead hassling with them.

[IGladlyDriftAZ31]

sounds to me like its your diff mounts i had a similar problem in a s13 hatch the driver wound up breaking the diff from where it mounts to the subframe in the 240 and before the fix it was acting similar to what you described