T-56 Questions

[TnBlkC230WZ]

I've done some research, but I'm still a little confused. Does the -011 aftermarket T-56 bolt directly up to a Muncie bellhousing? Does it have a mechanical or electronic speedo? I'm assuming a I need a special pilot bushing or does it work with a standard SBC pilot bushing? I have a 71 Nova, will I have to cut the floor brace or just the sheet metal to put it in?

If I find an old LSx T-56 to rebuild, can I change the OD ratios to .74/.57 or .80/.62 and leave the 2.66 first gear? I really like the 2.66 first gear, but would prefer a .57 or so overdrive.

[perple76]

I'll have to check my invoice for that part number, but if you are looking at the "aftermarket" GM T-56, you're on the right track.

I just installed this transmission in my '77 Nova, which has basically the same floorpan as your '71. Here are some things I encountered along the way.

None of the T-56s bolt "directly" to the Muncie Bellhousing. You must use an adapter plate. Your Tremec dealer will hook you up with the plate, but it is drilled from Tremec for the T-5 bellhousing. Your dealer can drill the plate for your Muncie bellhousing or I suppose you can have a machine shop do it. My dealer (Forte Parts Connection) drilled the plate for me at no charge and included it in the price of the transmission. These guys were pretty knowledgeable, by the way, and it would be worth your while to give them a call. Find them on the web.

I initially tried my standard SBC pilot bearing but was uncomfortable with the measurements I was getting out of it and wasn't sure it was seating properly. I ended up purchasing a McCleod extended pilot from Summit Racing ($37.69, part number 8617). I am much happier with this setup now that the tranny is in the car.

The T-56 I bought from Forte Parts is machined for your mechanical speedo out of the Muncie. The entire speedo assembly will simply slide into the T-56 with no problem. You may have to machine down the hold-down tab and find a different bolt but that's about it. The speedo housing is on the driver's side of the transmission, which for me made it easier. You will also need to do some research on which speedometer gear you need to go with, which is a science experiment in and of itself.

Everyone wants to sell you a custom tubular tranmission crossmember, but I didn't see the need. I used a crossmember from a TH350 automatic and it fit with very little modification. Custom weld in X-members can be found all over the place. I think JEG's has one for something like $80 if you don't mind the work. You might try your stocker first, though, to see how much modification will be needed. Save some money where you can, I say.

I think our floorpans are almost identical. If that's the case, get your cutting tools ready. You have to cut A LOT of sheet metal out of the floor to fit the T-56. This transmission is tall and long. Yes I had to cut some of the floorbrace as well to fit the shifter housing in correctly. This was one of the worst parts of the install but also one of the least expensive. I welded an entirely new tunnel (that I actually prefer to the stock tunnel) for less than $100 in materials. Remember when trial fitting the tranny that you want your driveline angles at virtually zero with the car at ride height. Otherwise you'll wear out a driveshaft or tail section of the tranny in no time flat.

You'll have to shorten your driveshaft but the rear of the tranny is set up for the 27 spline yoke that you should already have with the Muncie. I had my driveshaft shortened for less than $100 at a local shop. Most well-equipped shops can set you up with whatever you need in regards to u-joints, yokes, etc.

You will have to replace the clutch (26 spline instead of the Muncie's 10 or 22?) but can reuse the stock mechancial clutch fork and throwout bearing with this transmission. The adapter plate has a "throat" on it for the throwout bearing to slide upon.

Finally, there are two wiring issues on the T-56: the backup lights and the reverse lockout solenoid. The tranny does not come with the plugs you need to wire this into your existing harness. I found the plugs on Ebay - they were about $10 a piece.

Overall it took about 6 weeks to get this transmission out of the shipping crate and into the car, but that was only working on it an hour or two at at time and 3-4 days per week. You could do it faster if you're pushing it. Also expect to spend about $3K (maybe a little more) on the whole package. Obviously the tranny is the most expensive part but some of this collateral stuff can add up pretty quickly if you're not careful.

Hope this helps. Happy to answer any questions based on my experience in going through this thing.


J