T85 or T89? The R11 planetary gears and the rear splines...


http://209.208.111.198/Topic35404.aspx 		Print Topic | Close Window

By Daniel Jessup - 16 Years Ago
A couple of questions about the T85. I just purchased a very nice T85 case 3 speed with overdrive (R11) and the planetary gears are just about pristine - for those of you that were asking, yes there are four small gears around the sun gear. Very little wear and the whole unit itself itself is in really good shape. I am very pleased with what I have. Thanks Dennis and some of you other fellas for answering my questions from the other posts.

The case is stamped T85, but the cover plate says T89 and is squared off on top and has an entirely curved bottom (maybe I can post some photos tomorrow). The tail shaft splines have 31 not 16 like my 55-56 Ford passenger car driveshafts and drive train. It looks like this transmission is a complete bolt in to my bellhousing and my transmission crossmember or am I wrong on that one? The length from end to end looks identical as my 3 speeds too. What can I do about that 32 spline tailshaft - is this a 57+ yoke assembly? How will this mate to my original 55 56 Ford driveshaft?

By marvh - 16 Years Ago
That likely takes a 31 spline yoke.

These were used on the 63 Fords, 67 1/2 tons, 69/70 Cougars & Mustangs. Two speed aluminum case Fordomatic, C6 and FMX Transmissions used that yoke both with 1310 &1330 joints.

Cruise-o-matic used 28 spline yokes.



You will have to change the front driveshaft yoke.

Use 57 up driveshaft as it has a 1310 joint.

marv
By Daniel Jessup - 16 Years Ago
Marv,

thanks for the reply...I guess it is 31. I counted two or three times and thought that surely it was 32 - odd number, go figure.

Can I just use a 57 Ford driveshaft assembly, or should I take a yoke from a 57 Ford driveshaft, and then marry it to my 55/56 driveshaft?

By marvh - 16 Years Ago
A 57 driveshaft is longer than the 56 driveshaft. You will have to shorten it and attach the rear mechanical joint from your 56.

It is best if you measure the driveshaft length you need before cutting as I do not know what the length of the OD transmission you are using. You should have it re-balanced as an out of balance driveshaft can do lots of damage.

here is a link to a good site on drivelines.
http://www.iedls.com/home.html
marv
By Daniel Jessup - 16 Years Ago
Here are some photos of the T85? or T89? in question. It really is in great shape, and as you can see, those gears for the R11 look like they were installed last week. Does the T86 have its shift studs in line or are they staggered like the photo? I assumed they would be in line.

    

By marvh - 16 Years Ago
WOW that is a nice transmission. You are very lucky to find it.



I wish you could put it in a flat rate box and mail it to me.

marv
By Daniel Jessup - 16 Years Ago
Yep - flat rate! They would never notice the bulges on the sides and the tail shaft sticking out a little! Tongue Maybe a little duct tape would work...BigGrin
By crenwelge - 16 Years Ago
Its not a T86 because the T86 is the one with the tin lid and shifters built into the case. I think it is a T89 because of the staggered shifters. It is a very good transmission. It was used behind engines up to 390. Yours could have well come out of about a 64 model with the big engine. There was a year or so they used a goofy spline, but they are still available. I would get a yoke to fit it, shove it in about where it would normally go, measure the centers of the U-joint to the center of the U-joint on the rear and have a good drive shaft shop build you a drive shaft. An old Hurst Mystery shifter does real good on these transmissions.
By Ted - 16 Years Ago
Daniel Jessup (11/30/2009)
The case is stamped T85, but the cover plate says T89 and is squared off on top and has an entirely curved bottom......
The shift levers on the T-85 are inline whereas they are staggered on the T-89’s.  That’s the easy identifier.  On the inside, the T-85 uses helically cut gears for the first and reverse mainshaft while the mainshaft for the T-89 uses straight cut gears.