unusual driveshaft wear, ae85/86 LSD (updated)

[rollaholic]

so the LSD in my 85 has been making some new and interesting noises lately. i stopped driving it earlier in the week, and pulled the diff head out today.

some pics!

driveshaft inner splines

http://i29.photobucket.com/albums/c296/ ... 7_1409.jpg
http://i29.photobucket.com/albums/c296/ ... 7_1408.jpg

side of LSD

http://i29.photobucket.com/albums/c296/ ... 7_1411.jpg

these marks are unusual, im not sure what its been touching - the matching section on the other side of the LSD is unmarked

diff inner

http://i29.photobucket.com/albums/c296/ ... 7_1413.jpg
http://i29.photobucket.com/albums/c296/ ... 7_1412.jpg

out of interest, where do you measure from to determine if you have the large or small diff? and any ideas on whats causing that weird worn section on the inner side of the drive shafts? the diffs made a light, constant metallic sound from the day i got the car, similar to a brake wear indicator or maybe even a fuel pump. i figure this was the cause - its almost like the shaft is too long, though both sides appear to be the same length.

diff is getting sent to diff specs on monday for further inspection.

[jondee86]

Looks like that lump of metal was getting a lick from the nose of
the pinion gear. Could only happen if it was sticking out by a millimetre
or two past the carrier casting

Cheers... jondee86

[rollaholic]

the pinion gear appeared to be in good order - though presumably its hardened so might not show signs of wear if its been striking something softer.

it might be worth noting that on the right hand side of the car, i had to put spacers on the brake caliper cradle, to push it out from the bracket a few mm - the front of the disc was touching. it hadnt occured to me before, but is it possible the LSD isint centred properly or something? one axle pushed out, causing my cradle problem?

other side works ok without spacers however.

[jondee86]

I just had my diff apart (AE86 OEM LSD) and the ends of both axles
were definitely the same. From your pics you appear to have one with
a hole in the end And, according to some of the posters in this forum,
there are two different lengths of axles. Apparently you need to trim
the longer ones by 4-5 mm, to get them to fit in a diff that is built to use
the shorter axles.

Maybe someone replaced a short axle with a long one ? Certainly doesn't
look like you have a matching pair

Cheers... jondee86

[rollaholic]

sounds like a feasible scenario. sadly the axle has been doing its own trimming inside my diff guess i better get that end machined down...

[Mr Revhead]

measure the length of each axle and see if they are the same.
the axles are not left or right handed.
if the worn one is longer.... thatll confirm it.
but certainly looks that way to me

[rollaholic]

rev, where do the different length axles come from? is it facelift vs non? or just random longer axles?

[Mr Revhead]

lsd vs non lsd

im not sure if facelift/prefacelift are exactly the same lenght, but its the lsd vs non lsd you need to worry about

[rollaholic]

just went into work and took some measurements.

the worn one is approx 5mm longer than the normal looking one...

i wonder how much damage its done to the LSD.

are facelift axles hens teeth?

[Mr Revhead]

depends what you mena by hens teeth... theres stock at toyota in nz!

i have noticed that there appears to be far more preface lift parts sold than face lift though

[rollaholic]

what kind of price are they? theres a reasonably good deal on a TRD LSD on tardme at the mo, but its a facelift unit and i have pre facelift axles.

[rollaholic]

well, i got my diff back today.

the spider gear carriers on the side of the LSD ramps have been completely snapped off, leaving the ramps floating essentially - allowing one side to strike the pinion. (jondee hit the nail on the head).

im looking for replacement options, anyone got anything on offer? the LSD ramps are avaliable from japan at an estimated cost of $3000 so i dont think i'll be going down that path.

i see a pre facelift TRD unit on trademe, but it appears to be 1.5 way going by the part number.

what are the advantages / disadvantages of 1.5 vs 2 way?

[Mr Revhead]

wont be $3000

thats just listed retail, which wil be waaaay out as its a non stocked part in nz.
having said that i doubt itll be much less than a grand as you have to buy the whole carrier.

1.5 will lock up less under decelleration.
going from what you have now to one of those will be fine.
if it suits ya budget, jump on it