3 speed o/d strength

I have two o/d transmission's one has T-89 cast in the side of the case and the other is a side load with a 9 bolt cover on it. They are both ford transmissions. I am trying to decide which to rebuild.

 

are they R10 or R11? pic's always help. don't think they are full synchro and that ****s!

 

I think the T-89 is fairly light duty and has the lighter R10 OD.
Is the side loader one equipped with a curved lower edge on the sidecover? R-11 on OD?
if so, it is a T85, pretty stout, the stronger og the OD's, and the actual trans they used as the basis for the T-10 four speed.

 

In my experience, they are NOT the strongest trans in the world. For basic old car driving, you should not have an issue. I have run one behind a pretty well built Y-block for about 14 years and have had limited problems. It just isn't something i would be speed shifting with a bunch of HP.

 

The nine bolt cover is rectangular no curve on it. They both have R10F-1 OD units on them. Not gonna be racing them just want to rebuild one of them and not have to worry about it.

 

If your going to be racing then thats not the transmission you should be using, its only a light duty trans as mentioned above.

 

Thanks for the input. I think the side load case might be a mid fifties case. I will look inside and make the decision depending on which is in better shape to start with.

 

They are basically three speeds with synchro on the top two. The Od is a simple planetary gear set bolted to the back of the unit. They usually provide for about a 30% reduction in rpm in top gear. A lot of cars used the same basic set up attached to what ever 3 speed the manufacturer speced I believe the t 89 was used by studebaker, they used them in Champions, Commanders, Land cruisers and half ton pickups. Dodge and Plymouth used them in the R 7 and R10 version behind 6 cylinder engines from the mid 30's and again in the early 50's. Ford, and AMC used them also.

They can be set up to be on 2nd and 3rd gear basically giving the driver a 5 speed trans. If not engaged they play no part in the "strength" of the trans, as they are i p*** through mode. Since usually they would only be engaged in third gear cruise mode, the gear set strength during acceleration should not be and issue.

They are equiped with a governor, to prevent them being engaged at to low a road speed, and a kickdown to automatically take the out of line when WOT operation is desired.

I believe ther is a site where you can download a PDF of the service manual for the set up. and an operators manual as well. I don;t have it book marked so a bit of googling shuld do the trick.

I believe they were available behind the small hemi in Dodges.

 

Mopar and GM didn't offer OD on big blocks. Ford did in the 60's. I ran the ford OD behind a 360 horse 327 chev in a 56 ford for years with no problems. broke alot of ujoints and rear ends