Hey guys so I’ve been looking around but can’t find the answer I’m looking for. My auto 98 sc300’s diff blew up today and I’m just gonna swap another used sc300 diff in it, but I can’t find if a first gen diff will bolt straight up to my 2nd gen. I know that with the gs and supra the pumpkins work, but the flanges need to be swapped to bolt up. I’d imagine that all the sc300’s have the same flanges but I want to be sure before I drop a couple hundred on a used one. Personally I’m not interested in swapping flanges cause I know someone is going to say I should just do that and stop being a *****. Thanks!

 

It shouldn't be too hard to find a 1992-2000 SC300 A/T rear differential to swap in. They are all 4.272:1 ratio for all those model years and there would be no need to swap companion flanges. And the axle stubs also didn't change as far as I am aware.

If you can't find any SC examples for sale then you absolutely can use a 4.272 diff from a late 90's GS300 (I forget which years are 4.27 and which are 4.08) or a 93-96 Supra MKIV NA 4.272 rear diff. With either of those you do need to swap over your blown SC diff's original companion flange.

Did just your gears break? Is the cast iron case damaged and its bearing races? I'm wondering if the case itself might be a candidate for a rebuild provided you could get donor internals from a compatible diff.

 

Yeah this car has been a bear fixing all the issues. I’m not sure how but the teeth were pretty messed up from the previous owner, he told me that before I bought the car. Well while driving to work I heard a pretty nasty sound come from the rear and then a crackling metal sound, like BBs in a can. After I got home I drained the fluid and had some decent chunks come out. Dropped the diff and cracked it open and it looks like a few teeth got sheared off and the debris was ate up by the gears. Long story short it’s the spider gears and now I’m in need of a diff lol

 

Sounds like there were few to no diff oil changes over time perhaps. These SC/Soarer/MKIV/GS/Aristo diffs should have their gear oil drained and refilled with new 75W-90 GL-5 synthetic every 30k miles.

A driveline shop could tell you for sure if the actual housing is in good shape or not for a later rebuild. For now have you tried ebay? I see a few 4.272 SC300 Automatic diffs for sale there right now. All 1992-2000 SC300 A/T cars got the same 4.272 ratio open rear diff.