Ford Mustang Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
I have a 1966 A code mustang that has a Borg Warner T10 transmission. The transmission slips out of 2nd gear every time it is driven. I would either like to have the transmission rebuilt or perhaps replace it with a Ford Toploader. Any thoughts on which might be the best way to go?
 

·
Registered
Joined
·
8,021 Posts
Hello Dennis,

First of all, welcome to AFM.

A T-10 in a '66 Mustang is not a common occurrence but there were a few. That might, or might not influence your decision. I have one in a San Jose A-code and I just finished totally rebuilding it a couple of months ago. Because there weren't many of them you will find people telling you there never was such. Parts are more of a problem than for the toploader but what you need is likely out there. I am assuming yours is a '66 unit; do you know what the date code on the side of it says? Its important since '66 was different than any other year.

I am not at home now so am working from memory but I have nearly any information you need about what to do, how to do it and where to get the parts. Jumping out of 2nd gear is a quite normal problem for the T-10 but there is a very easy fix call a Torque-Lok slider. Provided all your gears are themselves in good shape, the bearings and all small parts are available and with a couple of tricks I can tell you about you should be able to make it work great. New bearings, sliders, countershaft, etc. are about $175 as I recall but you, or someone else needs to be able to take it apart and put it together again.

Ford in '66 (only) used a modified design that no one much remembers. The instructions in the '65 Mustang manual are NOT for a '66 since the mainshaft is made differently and the gears come out in a different manner. The change also caused a minor interference problem when used with the new sliders you will be buying but, knowing that in advance, the fix is pretty easy if you have a bench grinder. I have all the mods in pictures on my home computer.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
My mustang is currently at the restoration shop and I don't have tag number at hand. The mechanic is now advising me to swap the T10 out for a rebuilt T5. I am trying to consider all the pros and cons of various transmissions before I make a decision. My main considerations are "cost" (I am not doing work myself) and "fun" (I want it to be fun to drive). Thanks for your reply to my post.
 

·
Registered
Joined
·
8,021 Posts
The date I am talking about is stamped in the cast iron near the mid-plate and will be in a form similar to mine: G1162 - July 11, 1966, 2nd shift.

My total parts bill for all internal small parts, bearings, seals, synchros, Torque-Lok sliders and a new countershaft was $260 including UPS delivery. Much of that may not have been needed but I only wanted to do this once. It jumped out of 2nd on any downhill grade previously even if I was going easy. It does not jump out of any gear now no matter how hard or easy I treat it.

The '66 T-10 ratios are somewhat unusual at 2.64 / 2.10 / 1.60 / 1.00 / 2.71 Reverse. 1-2-3 are fairly close with a big step to 4th. Its sort of a close ratio 5-speed with 4th gear missing. You will likely never find those ratios listed anywhere, in any reference; I couldn't. There are many who claim to know the ratios but every one of them I found was wrong for a '66 Mustang.

The picture is of the date code in the lower right corner. It was taken to show a fix to correct a reverse idler clearance problem that these had way back when they were used behind 421 Pontiacs, etc. Some T-10s have this problem, others do not but its an easy fix to knock the corners off the countergear teeth.
 

Attachments

1 - 4 of 4 Posts
Top