Driveline backlash/vibration (GA61)

[mullett]

Driving to uni and back is driving me nuts in traffic, I've got a very viscious amount of driveline backlash, which is symptom one, and a nasty vibration above 6000rpm...symptom two.

I've swapped out the diff (because I had a known-good one, and the one I had whined...badly), which hasn't made much difference to the backlash. The tailshaft *seems* good, and the vibration (which might be unrelated) makes me think its a gearbox problem (as it occurs by RPM rather than speed).

Thoughts?

-RM

[oldcorollas]

is it a sprung clutch friction plate? springs popped?

there should not be any backlash in the gearbox unless it is fubar'd.
only the input shaft spins at engine speed, the other shafts are geared down.

if you put 1 back wheel up and spin it with car in gear, see if you can see/hear where the backlash is occurring

[pandaah]

dont have a dodgy harmonic balancer do you?.. when they wear they give horrible vibrations..

also, sounds like you need to either replace some bearings in the diff, or remove the pinion nut, replace the collapsable washer and adjust backlash accordingly

[wilbo666]

It is still there in 4th gear?


Have you checked the tailshaft center bearing is the right way up and OK?



Cheers
Wilbo

[RA35GT]

and also, hub centric rings yet? (i know its rpm related, just thought i would throw it in there).

[Muzza]

id do what the guys have said. in process of checking the diff like u have done
check ur rear suspension.
then check ur tail shaft
then ur clutch/gear box

[triptek]

Mine has a large about of backlash coming from the rear. I'v narrowed it down to the diff. It's made very noticable with the 5 puck clutch. It's still the factory 25 year old diff with 450rwhp going through it.

[mullett]

Oldrollas: Can't remember if there's springs in the centre of the clutch plate or not, it's an Excedy puck (5 puck I think)

Pandaaaaaaah: Not sure, but it's a possibility that I hadn't thought of. I intend to rebuild the other engine and swap this one out at some stage soonish though.

Wilbo: Not sure how fast I'd be going to do 6000rpm in 4th And it's a Veem one-peice tailshaft, no centrebearing to speak of.

Rudi: Not yet

Triptek: I guess it's still a possibility that it's the diff, and made more noticeable by the aggressive clutch (mine's pretty similar to yours)

At the moment I don't have time to pull it apart, I will in a couple of weeks though, so I want to get a good idea of what to look for by then Anyone got a good guide to setting the backlash in an F series?

Also worth noting that it was back-lash free when nathan had it, I've changed the diff and engine, but still has the same gearbox (which may have suffered between the two of us) and tailshaft...

-RM
-RM

[CELICASUPRA7M]

http://www.cygnusx1.net/Supra/Librar...aspx?S=RA&P=37

[RA35GT]

and the same half shafts?

[mullett]

Well...I believe so...can't see someone going to the effort of taking them out

-RM

[Admiral coFF33]

subframe bushes cluncking (as subframe is moving slightly) as they are worn out?

my GF's MA61 does this ^^

[mullett]

All new polyurethane bushes Did you have any luck with a tailshaft?

-RM

[Admiral coFF33]

i did mate! thanks for the hookup!
runs like a dream now!

[pandaah]

this car been fixed?