95R transmission input /output splines

[Ron 1995 R]

I'm confused.

The transmissions in our cars have tag:
top line TR3550-3
btm line 2600709

The output shaft is 28-spline

the confusion comes in here:
- some Reputable sources say the input shaft is toploader style 10-spline
- some reputable sources say it's The updated 26-spline and that it's unique to the 2600709 making it capable of 425ft#tq

Q1). does anyone here know what the input/output spine counts are?
(from actually pulling the transmission or replacing clutch)

Q2). Can someone confirm the output spline count as well?

...There is nothing I found on google or on the tremec webiste on this transmission tag TR3550-3 2600709

Thank you.

 

[Cobra R Man]

The original '95R Tremec trans had 10 spline input, and 28 spline output.
Tremec updated the 3550 with 26/31 spline respectively, for higher torque capabilities. :beer:

 

[tomshep]

+1.

Tom

 

[Ron 1995 R]

So 10-in/28-out is good to know.

Tremec must have their own books messed up, unless I have a different transmission than the other R-cars have. Again my tag is TR3550-3 and 2600709. (Guy at tremec stated the 2600709 had the 26-spline input as they new the cars were being intended for road racing)

I agree all the other six (known) 3550 cases had 10i/28o spline count.

Guess I need to find a TCET1377 case (3550-TKOII) if I want to make the .82 gear swap efficiently. Apparently Tremec doesnt make the .82 28-spline output/mainshaft anymore. Everything is TKO600 31-spline and with the 31 spline the 31-spline yoke wont fit the tailshaft opening so that needs to be hogged out. I'm not interested in hogging out the tailshaft. :dw: ...unless someone else has been here and has a better idea oke:.

The ford part numbers for the transmission (F5ZV 7003 BA) and clutch disc (F3ZR 7550 AA) dont mention spline counts.

Thank you for verifying as it paves my direction forward (without pulling my trans in the meantime) :coolman:.

...

 

[tomshep]

Are you SURE you have the stock tranny in there? Either tranny is wrong or for some reason the correct tranny has the wrong tag.

I know it is more money but why not go with a new tranny?

You are probably going to have darn near half the cost of it by the time you are done anyway, IF it all comes together correctly.

I thought the new TKO was available with a .82 O/D using the 10/31 spline. That way all you change is the yoke on the driveshaft. Even if you have to go to a fine disc all you do is swap the disc, not the entire clutch.

I went to a .82 with the 26/31 a long time ago and have been very happy.

Tom

tom

 

[Ron 1995 R]

I was thinking new trans. The drawback is the 2.87? First gear on the .82 5th. To get the first gear leverage back I need to swap rear gears as well as clutch disc.

...but yes it is a viable option. I haven't found a new tremec with a 10i/31o and a.82 5th.

 

[Cobra R Man]

Unless you're drag racing, first gear is just to get you out of the pits, or moving from a traffic light. The trans. in the Ford Racing catalog (M-7003-R58C) is still close ratio :rockon:, for road racing:beer:, with the .82 fifth. :shrug:

 

[tomshep]

I was thinking new trans. The drawback is the 2.87? First gear on the .82 5th. To get the first gear leverage back I need to swap rear gears as well as clutch disc.

...but yes it is a viable option. I haven't found a new tremec with a 10i/31o and a.82 5th.

It has been a few years since I went down this road, but I did mine right when the TKO 500 and 600 had come out. I don't remember the differences but it all had to do with input/output splines and the o/d ratio.

FYI, the 3550 is 10/28. Back in the day they offered a 3550 TKO that went to 26/31 as I recall. Then they dropped them both and went to the 500 and 600.

For me, the easy choice was a new yoke and new clutch disc.

Tom

 

[598]

You mentioned spline changes for increased torque. I hve been debating putting in a different engine in my 95 R to protect the # matching original, as well as a lot more torque for the track beatings. In you guys experience, will the stock 3550 trans take 500-550 ft. lbs. of torque in a mostly track car?

Thanks,

Steve

 

[Ron 1995 R]

According to tremec it's good for 375- 425 engine torque on street tires (not slicks) depending on input shaft spline count, 10 or 26

 

[Cobra-R]

You mentioned spline changes for increased torque. I hve been debating putting in a different engine in my 95 R to protect the # matching original, as well as a lot more torque for the track beatings. In you guys experience, will the stock 3550 trans take 500-550 ft. lbs. of torque in a mostly track car?

Thanks,

Steve

Do a search.....Many of us have has the original transmission cases crack and leak oil, after that they break third gear. (from track use, I assume)

I would buy a good tranny like Tom mentioned and keep your original....original.

Brian

 

[tomshep]

You mentioned spline changes for increased torque. I hve been debating putting in a different engine in my 95 R to protect the # matching original, as well as a lot more torque for the track beatings. In you guys experience, will the stock 3550 trans take 500-550 ft. lbs. of torque in a mostly track car?

Thanks,

Steve

Short and simple answer--NO.

The 3550 is marginal behind a lightly modded 95R. Start adding power and beating on it and it will fail. 3rd gear goes.

Bite the bullet and save yourself headache and money later on. Put a TKO in it.

Tom

 

[Robert M]

Are you SURE you have the stock tranny in there? Either tranny is wrong or for some reason the correct tranny has the wrong tag.

Tom

Tom - If it is the correct original Ford assy. line installed 95R transmission, shouldn't it have a portion of the VIN (the lead letters and seq. number) stamped in the pad on top of the case, just ahead of the tailshaft housing?

R

 

[tomshep]

Oh yeah, good point Rob.

Forgot about that one. Look on the driver's side of the shifter turret. The VIN should be stamped in there so you would at least know the tail shaft is original.

Tom