Transmission/rear rebuild

[merc123]

My 5th gear and reverse went 5,000 miles after Ford fixed it the first time. My rear end also died in that time frame and Ford denied the warranty because of the 3.73's gear they put in for me. So anyway, long story short. Looking at getting a new, rebuilt 3650 instead of getting my current one rebuilt.

What do you think about the Promotion Powertrain 3650? I'm looking at the reconditioned 750hp model with 26spl input, TSB and beefy shift forks. I know my car may not see 750hp, but I figured for the extra $400 I can potentially beat on this tranny and not worry about breakage. I'll also wind up finding a 26spl clutch for it since I have close to 80k on mine as it is. What do you think?
ProMotion Powertrain


Also, swapped my old rear end for a used one out of a wrecked stang for $200, but it has 3.27 gears. Looking at getting the PMP 8.8 heavy duty rebuilt rear, 4.10 or 3.73 gears, 31 spl T-loc w/ carbon fiber clutches, main cap stud kit, TA performance girdle, Moser hi alloy 31 spline c-clips, welded axle tubes and master bearing and seal kit for $1,679. It looks like it'll be cheaper (parts wise) than building it myself.
ProMotion Powertrain


Not to metion they'll have a new shop in NE Atlanta soon so I can save on shipping.

 

[COramprat]

I guess it depends on your willingness to pay the price. If you are willing to spend the extra for the upgrade that is up to you. Personally I'd be happy with the reconditioned one at 1250.

I've beat on my T45 and only had to replace a shift fork at 130,000. It is showing it's age now at 198K miles but I attribute it more to the guy I had for the shift fork replacement than any wear I've put on it. It hasn't shifted right since I got it back from him and has only gotten worse in the last few months.

I'd think if you are not planning on anything substantial as far as go-fast mods that you'd do better to save your money.

 

[merc123]

Well, the stocker ran until about 85k miles with me "beating" in it... The clunk TSB at 20k was the first service it ever had and didn't need anything again until the tranny broke at 73,466 miles (and again at 78,784).

I guess I could just go with the "stock" rebuilt one. I'm assuming they know what they're doing, I don't trust anyone around me to do it.

 

[02nightmaregt]

My 3650 lasted to about 77,xxx or so and i had it rebuild. It had been grinding 3rd for about a year and a half though. The guy that rebuilt it told me it was only a blocking ring that was bad and the syncro and gear looked good actually. Now im at about 85,xxx and its running good. I never could find any kind of rebuild kit for it.

 

[bobc83]

I'm in the same boat as you Merc123. I would really like to know if anyone has good things to say about the 750hp 3650, as I would be interested in one too. Also, it lists a carbon synchro upgrade as well but I don't see it in that tranny, wonder if it's included.

 

[NX281GT]

That PMP rear looks like a good deal, especially when you factor in labor costs. I put Moser 31's, an FRPP 31 spline T-lok, Motive 4.10's, Master install kit, new wheel studs, and a Trick Flow girdle for around $1100 doing it all myself. I still gotta get my tubes welded too.

 

[SilverBullet00]

I'm in the same boat as you Merc123. I would really like to know if anyone has good things to say about the 750hp 3650, as I would be interested in one too. Also, it lists a carbon synchro upgrade as well but I don't see it in that tranny, wonder if it's included.

It does include the cabron fiber syncros in the built 3650. I have called and talked to them about it. If you plan on making north of 400hp you need something different then the crappy stock 3650. I broke mine @60,000 miles on street tires at the track, on my first pass with the supercharger.

The only downside to the Promotion 3650 is it doesnt have an SFI approved bellhouse available.

 

[bobc83]

So they don't come with the bellhousing? Can't I just use my stock one?

 

[SilverBullet00]

They come with the bellhousing, its just not SFI approved. If you plan on running your car at the track... or if you like you toes, you should get a tranny that has an SFI approved bellhouse available.

 

[merc123]

What if you keep your car stock and not really race it think the bellhousing will be alright?

 

[merc123]

I went with Rebuilt Transmission | Manual Transmissions | Mustang | Truck

They sold me one for $1130 ($200 core charge, $200 shipping to me and core back). 1 year warranty also.