The TR-3650 into SN-95 Cobra swap thread

[CJK440]

I have a decent T-45 out of my car now that I was going to rebuild but then I get to thinking about swapping it in favor of a TR-3650 with the 10% or so higher torque rating. I'm assuming this is a favorable swap.

Problem is there is no authorative swap thread or article for one of these into our cars that I can find, just bits and pieces. To complicate matters worse, putting a TR-3650 into a GT is easier than an SN95 cobra.

So from what I gathered I think the following is correct but please correct me if I am wrong.

The TR-3650 will bolt up to the engine fine
Clutch is the same between T-45 and TR-3650
The shifter assembly will not interchange.
The driveshaft is the same.
The reverse light setup swaps over easily
The speedo will no longer work but a Speedcal from Dallas Mustangs will fix this easily.

Now onto what I thought was the most (relatively) complicated part.

All TR-3650's have the 96-98 "GT" transmission mount location on the tail housing, not the rearward 96-98 "Cobra" location so this needs to be adapted on Cobras only.

On my car I welded the tranny mount brackets to the frame rail following FLSFC install so I cannot simply slide the brackets forward and redrill. I'd have to cut them off and reweld. I suppose I can do that if I need to.

Did anybody come up with a tranny mount adapter to use a tranny with a "GT" tranny mount location with the Crossmember in the Stock Cobra position????

My apologies in advance if I happened to miss an all inclusive swap writeup/thread.

 

[RIO RED SNAKE]

+1, i want to do this or a t-56 down the road it woudl be nice to know

 

[96dreamer]

i put a 3650 in my car, i just swapped tail housings between the transmissions and everything bolted up fine

 

[CJK440]

i put a 3650 in my car, i just swapped tail housings between the transmissions and everything bolted up fine

What tailhousings? As far as I can see all TR-3650's had the "GT" tranny mount location.

I can see the tail housing swap being done to put a "GT" T-45 into a Cobra by swapping the Cobra T-45 tailhousing on. Unless the T-45 and TR-3650 tails interchange?? Stranger things have happened.

 

[CJK440]

I think this is fairly common knowledge but to illustrate the differences between an SN95 GT and Cobra tranny mount location.

T-45 out of an SN-95 cobra

T-45 out of an SN-95 GT. I also think all New Edge cars 99 & up (GT's and Cobras) share this same location.

I never got a straight answer on why Ford decided to change this on the SN-95 Cobras. Perhaps exhaust or cat converter fitment??

 

[harvboi05]

wow, its a good thing you just posted those pictures. i didnt realize the mount difference. i might have to swap tailhousings this weekend.

 

[96dreamer]

they interchange ive done it. swap the tailhousings of the 3650 and the t-45. i had a cobra t-45 with a broken reverse and fifth gear. i got a a 3650 out of an 02 gt and swapped the tailhousing so the 3650 had the cobra tailhousing and bolts right up

 

[98SVTslobra]

the t45 and tr3650 tail housing are interchangable? i thought they werent? :shrug:

 

[CJK440]

the t45 and tr3650 tail housing are interchangable? i thought they werent? :shrug:

More research. The center distance between the mainshaft and the cluster gear is wider than a T-45, this allows bigger gears and more torque capacity. Since the bearing races are in the tailhousings, I don't see how they can interchange. The bearing locations would be off.

96dreamer, sure it was an 02? From what I understand Ford switched from T-45 to TR-3650 mid year 01.

 

[Sh!tstang]

Not trying to steal the thread but would I be able to change tailhousing from my 97 Cobra t-45 to a GT t-45 tailhousing? Would it affect anything?

 

[RIO RED SNAKE]

More research. The center distance between the mainshaft and the cluster gear is wider than a T-45, this allows bigger gears and more torque capacity. Since the bearing races are in the tailhousings, I don't see how they can interchange. The bearing locations would be off.

96dreamer, sure it was an 02? From what I understand Ford switched from T-45 to TR-3650 mid year 01.

yea 01 and 1/2 they changed to the 3650....then obv from then to 04...but before 01 and 1/2 they were t45s..so idk

 

[96dreamer]

i was told it was out of an 02 i suppose he could have been mistaken

Edit: did some more research on it and seems you guys were right, guess i just took the guys word for it. so if your trying to put a gt tranny in a cobra just switch the tail housings lol

 

[firemedix911]

You r right. You have to relocate the mounting bracket. Cut it from where u have and place it where it will fit the 3650.

 

[F8L BYT]

The clutch's are NOT the same... T45 is a 10.5 inch clutch and the T3650 is a 11 inch.... Another thing to note is ford also had an update on the 3650 in 03/04 and they are much much better. They also have a longer 5th gear which really really helps if you have a steep gear in the rear end

 

[CJK440]

The clutch's are NOT the same... T45 is a 10.5 inch clutch and the T3650 is a 11 inch.... Another thing to note is ford also had an update on the 3650 in 03/04 and they are much much better. They also have a longer 5th gear which really really helps if you have a steep gear in the rear end

Is the input spline count and diameter the same between the two? That is typically the big indicator. If they are the same and the splines engage, what would stop you from using a TR-3650 with a 96-98 Cobra clutch??

 

[RIO RED SNAKE]

ya the 5th gear in the tr3650 is longg!!!!!! 355s to the tr3650 in a 03 mach equals 80 mph at 2050 ish rpms...my t45 with 355s at 80 equals like 2300 i think...sucks

 

[harvboi05]

5th in a 3650 is either .62 or 68 as listed per Tremecs site.

5th in a t45 is .67.

 

[DVJ38]

ya the 5th gear in the tr3650 is longg!!!!!! 355s to the tr3650 in a 03 mach equals 80 mph at 2050 ish rpms...my t45 with 355s at 80 equals like 2300 i think...sucks

Try 4.30s lol

Well this is a good thread. I know now I don't want to rebuild my t45, but go with a newer version of the 3650 atleast for the longer 5th gear.

 

[F8L BYT]

Is the input spline count and diameter the same between the two? That is typically the big indicator. If they are the same and the splines engage, what would stop you from using a TR-3650 with a 96-98 Cobra clutch??

I mean yeah they are the same spline count and diameter so it will technically work but whats the point really? I would rather put in the right parts so save any problems and possibly having to do it again.

Try 4.30s lol

Well this is a good thread. I know now I don't want to rebuild my t45, but go with a newer version of the 3650 atleast for the longer 5th gear.

Definitely! That or a t56

 

[CJK440]

I mean yeah they are the same spline count and diameter so it will technically work but whats the point really? I would rather put in the right parts so save any problems and possibly having to do it again.

Saving money is probably the biggest reason. If you have a clutch & flywheel that is problem free in front of a T-45 then why change it? Especially if you spent the money for an aftermarket unit. It will behave the same in front of a 3650.

Now if your clutch is toast or not up to the task of your modded engine, then might be a good time to upgrade to the larger one.