MA61 W58 F313. Whining, help diagnose driveline/diff problems?

[AE25]

if only shipping from aus wasn't a killer! would love an 8" torsen.

[patrickleslie]

Cheers for the wall of info, that's very helpful!

From all that I can 99% definitely conclude that the input shaft bearing on the gearbox is the cause of the loud whine. Too bad for me but that will have to wait a while for a permanent fix, although I will keep in mind to perhaps try a different/more approriate weight oil, thanks for the idea 4th Surf. Is it possible to replace the input shaft bearing from the outside without splitting the gearbox, or does it require a full rebuild to do?

What I'm getting from reading all that regarding the diff is that either the C&P isn't mating properly (less likely), or the spider gears arent mating properly (more likely), or the axle splines (i'm gonna say less likely because they didn't move when I turned by hand), or a combination of all 3. I'm also going to go with the assumption that the clutch discs aren't amazing, being 29 years old and all, and this is also adding to the problem.

So I see 3 options to getting this sorted:

Rebuild the current diff. Shim it up tighter than OEM, and be a billionty times better than anything I've ever driven in this car before. As for the wearing out, I'm sure it will happen but the time it would take to wear out back to where it is now...well I dont think that will be a major problem for a long time...?

Fit a TruTrac. This seems to be a well worn path, at least on CS.com. And no clutch parts to wear out. However I am very much aware of the issues when you lift a wheel. I have a steep driveway and I lift a wheel twice every day. This doesn't exactly make me keen on the idea.

Fit a TRD centre. Apparently it's a front diff for an Altezza or something and it fits nicely in the MA61. Clutch type 2 Way is probably way overkill for the 5ME, but if the planned 2JZGE gets fitted down the line then this should be good to handle that, and I doubt it will wear out by then, or even soon after then.

4th Surf I have IRS not live axle but I'll definitely look into those other Toyota options too

I'm leaning towards a straight rebuild but the TRD centre is tempting even if a hundred or two $$ more. There is a lot of things being said that I don't exactly understand so regardless it will probably be something where I drop it out, dismantle it, have a look and then decide it's too hard and send it to a shop

[patrickleslie]

And to clear this up, is a tight F313 diff what you might call a '1.5 way' diff?

[AE25]

And to clear this up, is a tight F313 diff what you might call a '1.5 way' diff?

no. 1, 1.5 and 2way lsd have ramps on the pinion shafts which wedges outward and loads the clutches when the axles spin at different rates. The angle of the ramps signifies what 'way' it is.
The oem diff is spring loaded instead of ramping and thus not the same design. Once the clutches start spinning, it is only the spring tension against the clutches that applies torque to the non spinning wheel.
A way to improve them is fit a stronger spring and/or washer under the spring. But don't overdo the tension as the F series lsd center plates have been known to break.
Also the live axle F series lsd is a better design than the IRS version. the irs only use the inner clutch plates and the two outer plates are just packers. not kidding! The live axle version found in cr30 4wd liteace and masterace-surf have teeth on the i.d. of middle plate so that it uses all 3 plates per side. (as seen bottom right in pic) You can update the irs version by swapping the middle plate for the toothed live axle style. weir performance in the states make rebuild kits doing exactly this. http://weirperformance.com/

Or make your own clutch plates. The std plates are hardened though. we've done exactly this so have a cad drawing if required.

[AE25]

also re altezza torsen. they're in the rear being rwd. but it's the sxe1# and gxe1# that have the 7.5". 2jz powered jce1# can have an 8".

[patrickleslie]

I think you've sold me on that, the weir kit looks a lot like a proper working version of the idea I had way back in post #7 about the extra clutch plates. I'll flick them an email and get some more info about what's included and what seals/bearings I'd need to get to suit, THANKYOU Mark!

[RyleyMA61]

Well, I just checked my ringgear backlash.

0.25mm

According to the TSRM, the spec is 0.15-0.18.

It says to adjust the backlash by adding washers either side of the differential ringgear/centre assembly.

Anyone done this before?

Any suggestions?

[AE25]

i'd suggest to download/ get hold of a toyota workshop manual for the ta6/ra6 celica/carina which has the irs lsd diff rebuild guide. there's other things to check, like bearing preload and most importantly the contact patch between the pinion and crown wheel (ring gear) which if it's out will cause a whine or other issues. 0.25 is not bad if the contact patch is good. if it's not making noises and you don't need to pull it apart for other things then i wouldn't worry about it.

[RyleyMA61]

Thanks mate.

It is a bit noisy - hence me checking backlash.

Has some clunk on accel/decel at low loads... but was worse as the diff oil got hotter, which suggested a change in oil viscosity. I'm changing to a redline synth oil so that should help.

Also has a whine at 70kmh - previous diff specialist suggested that it was slight wear on CW&P, but overall, the teeth look pretty good.

It does have a Trutrac Torsen LSD, so they are a bit noisy as well...

But while the diff is out, I wanted to check and make sure everything is OK before putting it back in.

I'm using this as a guide:

http://www.cygnusx1.net/Supra/Librar...ection=RA&P=18


Any other insights?

Thanks for your help.