M21 vs T10

x Baldwin Motion · #1 03-21-2010, 04:17 AM

my M21 is still in the VerySlow Transmission Shop, I have inherited a T10 from a later Camaro. I have a fat fine spline yoke to change on my driveshaft, but are the cross member mounting locations and the length of these transmissions the same?

as always, thanks in advance for the smarts

Keith Tedford · #2 03-21-2010, 06:30 AM

It's been a few years but I swapped out an M20 for a Super T10 in our'72 Lemans Sport. It had the factory Hurst shifter. As I remember it was a straight across swap with minor bending of one shift rod. Everything else bolted right up. I think the slots in one set of shift arms are longer than the other so you can switch one way but not the other. The ST10 worked just fine.

x Baldwin Motion · #3 03-23-2010, 06:50 PM

Now the M21 needs a new case. I am told the T10 bolts up but is two inches longer in the tail section. Need a shorter driveshaft now if I want to use the T10 (which he says is tough and like new inside).

Used driveshaft and have it cut, or measure and try to find the correct size? anyone have suggestions?

thanks.

396L35 · #4 03-23-2010, 06:55 PM

Nothing wrong with using the T10 and you can get some low 1st gears. Mark

**John Brown** · #5 03-23-2010, 07:03 PM

[ QUOTE ]
Now the M21 needs a new case. I am told the T10 bolts up but is two inches longer in the tail section. Need a shorter driveshaft now if I want to use the T10 (which he says is tough and like new inside).

Used driveshaft and have it cut, or measure and try to find the correct size? anyone have suggestions?

thanks.

[/ QUOTE ]

Time to get out your yard stick. I've never seen a T-10 that was a different length than a M20/21 (except for the odd Pontiac Muncies) so don't take anyones word for it. Otherwise, you'll cut your driveshaft three times and find that it's still too short.

**Fast67VelleN2O** · #6 03-23-2010, 07:13 PM

They are the same length. You won't need to shorten your driveshaft. What ratio is your Super T10?

Smokey · #7 03-23-2010, 07:50 PM

How about sell your T-10 to fund the Mucie project?

x Baldwin Motion · #8 03-23-2010, 07:57 PM

[ QUOTE ]
What ratio is your Super T10?

[/ QUOTE ]

Can I find out from the outside?

It's from an 80 Z28 allegedly, if that's a clue.

x Baldwin Motion · #9 03-23-2010, 08:08 PM

budnate · #10 03-23-2010, 08:23 PM

those are good with like a 3;73 gear, I think there 2;88 first gear??

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