T-10 bolt patterns

[irish]

There is a lot of confusion on this because well, it is confusing! I have owned several (still have a quite a few) of the Studebaker 4-speeds. The 1961 and 1962 T-10's all have the GM bolt pattern. The 1961 and early 1962's have the close ratio 2.20 first gear. Now to make it more confusing, from the cars I have seen it looks like the Hawks switched to a wide ratio 2.54 first gear earlier in the 1962 model year than the Larks did. So, if you have a 1962 it will have the GM bolt pattern but depending on when your 1962 was built it will have either the 2.20 or the 2.54 first gear. The 1963's and 64's all have the Ford bolt pattern and 2.54 first gear. Although I have ran across some info indicating you could still order a 2.20 first gear I haven't ever seen one in a 1963-64 Studebaker.

Joe

1961 and all 1962 T-10s were GM wide bolt pattern. '63 and '64 were Ford/Studebaker pattern.

[GinettaG12P]

From the foregoing, is it safe to assume that my 1963 Avanti R2 has a T10 with a Ford bolt pattern and a 2.54:1 first gear, or are Avantis different?

[Stunt]

Studebaker installed some 200 GM pattern wide ratio 4 speeds in '62, I believe, according to the parts book. I have one rebuilt and for sale. I'll be off-line for a few days.

WCP, PM sent.

[irish]

The first roughly 200 1962's are the GM pattern but they are the close ratio 2.20 first gear versions. The remainder (and the majority) of the 1962's are the GM pattern with the wide ratio 2.54 first gear transmissions.

Studebaker installed some 200 GM pattern wide ratio 4 speeds in '62, I believe, according to the parts book. I have one rebuilt and for sale. I'll be off-line for a few days.

[WCP]

Irish is correct. The late '62 Hawks got the 2.54 1st with the GM pattern case.

[Xcalibur]

If you already have the GM pattern bellhousing, you might wish to look at the GM T-5 five-speeds, as well. I'm on the road at the moment and don't have my manuals at hand, but google would let you know which first-gear ratios were available in what.

[Quentin]

1961 and all 1962 T-10s were GM wide bolt pattern. '63 and '64 were Ford/Studebaker pattern.

I have a 63 with a dud Stude FOM. Are there any other Ford boxes from this era that will bolt straight on? Any autos, i.e FMX?

[HawkBuilder]

I posted yesterday with the question about T-10 rear mount. My T-10 is from a 62 Hawk, GM bolt pattern. Is there a way I can tell from the stampings on the case if I have the close or wide ratio?

[Alan]

Best way is to pull the D cover off the side and count the teeth.

[clonelark]

I seem to remember that one of them had a ring or maybe 2 rings cut into the main shaft. i forget which one it was.

[irish]

That's right, The 2.54 first gear has one groove (or ring) cut into the input shaft splines. The 2.20 first gear doesn't have any grooves in the input shaft. Click on the pic I attached and you can see the groove I'm talking about.

Joe

I seem to remember that one of them had a ring or maybe 2 rings cut into the main shaft. i forget which one it was.