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Drivetrain Upgrade Time (T5)


Active Member
So my fastback has a close ratio toploader and 3.25 gears in it currently. The toploader I got for a song and dance, and while it's an absolute blast to drive once it's moving, it's a bear on the street. First is way too tall, and it runs at about 3200rpm @70mph. Commuting through Sacramento traffic is...unpleasant.

A few days ago I stumbled on a local ad the other day for an Astroperformance A5/T5 transmission. Went to look at it today, verified that it was indeed what it was claimed to be, and came home with the transmission, a Pro 5.0 shifter, a Centerforce dual friction clutch with 5000mi on it, and a fox body T5 bellhousing and clutch fork for $1500.

The transmission does need a rebuild. Some of the synchro rings are pretty beat up and the input shaft has a lot of front/back play, but the gears themselves appear to be in good shape.
Looks like I'll need to pick up some rebuilding documentation for these things.

I'm super stoked about the accessories that came with the transmission. The Pro 5.0 would have been one of the three options for the swap (along with Steeda Tri-Ax and MGW), the clutch is better than what I likely would have put in it, and the bellhousing is needed for the cable clutch conversion (Modern Driveline) which will hopefully be going at the same time as the transmission rebuild.

Looks like I've got my work cut out for me for a bit :)


Always on vacation!
Gonna be fun. I had a TKO600 in my 65 FB. Loved it with the 353 gears.

My 67 has a T5 in it with the stock 300 gears. I love it.

You will have fun with that T5.


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Active Member
Pictures will definitely be forthcoming. But I need to pick up a manual and rebuild kit before I can tear it apart.

I have to say, it's really nice being able to actually pick up the transmission. I'm not exactly in fantastic shape, and I could barely lift the toploader when I was in good shape. The T5 is light enough that I can easily pick it up and throw it on the work bench.


Active Member
Teaser pics. Disassembly pics will have to wait, as I'm not going to pull it back apart until I have the rebuild kit on hand. I also need to pick up a bearing separator and figure out what to do about a press...



I Don't Care. Do you?
They don't come any easier in terms of rebuild than a T5. Make sure you buy a quality rebuild kit. Lots of cheap junk out there. If it truly has Astro shafts and gears you got a hell of a deal (provided all in good shape). It will be a bit noisier than stock. The cut angle of the gears to blame but that's what allows them to take more torque without breaking. Everything is a trade-off. Is it a WC style case? They use better bearings in some areas.

Sounds like a great time to invest in a cheap Harbor Freight press. You can usually get one for just about $100 with coupon. Couple jobs as DIY vs paying someone makes it a win.


Active Member
I'll be buying the astroperformance rebuild kit. Seems to be the best bang for the buck, with good Timken bearings.

The gears are definitely not stock, and the case has a number stamping added by Astro, but haven't been able to verify yet which build it is. Gears look pretty good though.

It should be a WC case, but honestly not sure how to differentiate. It supposedly came out of a V8 fox body originally, along with the bellhousing.

Noise is less of a concern. The rest of the car makes enough to drown it out :)

I have access to a press at work, and at my father in law's shop, but neither of those are at my house, so on the fence about how I'm going to handle that.