Need Built 5R55S

[RielyHodge]

I am looking for parts to rebuild my 2005 Mustang GT. I know most people would say to get a different transmission, but I am hoping that somebody knows about a built 5R55S that can handle 800+ horsepower. The reason I am hoping that there is one is because this will be my first build, and I am already rebuilding the engine and fabricating an exhaust for twin turbos, so I am hoping that there will be one less thing to learn how to do.

 

[KLJ777]

Hey I am on my 3rd 5R55S and they are a pain. I found this company https://www.levelten.com/product_p/mustang transmission.htm I put out a little over 500RWHP and race a half dozen times a year. So far so good.

 

[07 Boss]

Level 10 is probably your best option, then TCI, but either way they might not be able to suit your needs. One of the issues is these synchronous trannies are a little more complex and you can only fit parts that are so big into them. I swapped in a Level 10 "bulletproof" tranny when I added my blower only to fry the 3rd gear bands a couple years later. Since then I found a local shop that builds trannies for a lot of local monster truck and dessert 4x4 teams and the owner, after explaining the abuse it was going to receive, gave me a 3 yr warranty even though it was a track car. Haven't had an issue since. If you are doing a serious build I might recommend moving away from the 5r55s. Other wise I would go with someone local and reputable to build it. If it were me I would call someplace like Monster Transmissions and see what they can mate to a 4.6 l 3 valve. I know they don't do a 5r55s but I'm sure they have some idea what would work best for your desired application.

 

[RielyHodge]

Hey I am on my 3rd 5R55S and they are a pain. I found this company https://www.levelten.com/product_p/mustang transmission.htm I put out a little over 500RWHP and race a half dozen times a year. So far so good.

Did it come with the torque converter, or do I need to find one?

 

[07 Boss]

Did it come with the torque converter, or do I need to find one?

Nope, you have to find your own. I went with a Precision Industries one but many here like Circle D.

 

[Laga]

I went with TC and hardened input shaft from TCI.
Your options are limited on the 5R55S. They don’t make that many upgrades and there isn’t that much extra room inside for HD parts.
I went with this kit 2 years ago and it’s handled my 500 RWDHP find so far.

https://globaltransmissionparts.com/5r55s-5r55w-transmission-super-master-rebuild-kit/?gad_source=1&gclid=Cj0KCQjw2N2_BhCAARIsAK4pEkXl9t4WsF4qhHBfcrBcyPkR7zi2qlz9kj_ELxi1O61Okq0KtGbfKscaAsSrEALw_wcB

Had a local shop do the work. With only 60K miles on it. They said the servo bores had a lot of wear.

 

[05stroker]

At 800 rwhp the 5r will never live. I tried this years ago and started snapping billet input shafts ant this level.

 

[07 Boss]

At 800 rwhp the 5r will never live. I tried this years ago and started snapping billet input shafts ant this level.

That was my thought. That's why I suggested going in another direction for anything serious.

 

[RielyHodge]

800 hp is the limit of what I am going to push, my goals are really around 700, I just want to make sure that if I do push more hp I'm not going to break something, the level 10 5r55s says it can handle 1000 hp, however, you guys are saying that isn't likely. Like I said, the car is already automatic, otherwise I would be putting a T56 Magnum XL in it, but manual swapping it seems like a pain. Especially since I will already be rebuilding the engine, fabricating an exhaust, and replacing almost everything else in the car. So which transmission would you recommend using that I could easily swap into the car without needing TOO much stuff?

 

[05stroker]

A T56 swap is not any more work the any other trans swap. If you want to stay auto then a 4r70w or 6r80.

 

[RielyHodge]

Is there any swap kits to make a 6r80 swap easier?

 

[JC SSP]

Post some pics of your build buddy.

 

[RielyHodge]

Post some pics of your build buddy.

I haven't started anything yet, right now I am just sourcing parts to get an idea of how much I am going to need to pay for it, right now I am stuck on finding a good transmission that won't require replacing a bunch of other stuff along with the transmission, but the car is going to be pretty much stock when I do the transmission, the only thing will be a built motor

 

[Autokyrios]

I have TCI's top 5R55S build. I can vouch that it's a good piece. I'd call them and chat.
For TC's, TCI and Circle-D are the ones that I know of. I run a TCI unit. I helped a buddy of mine with a Circle-D and it seemed good as well. In either case I'd call and chat to make sure you get the right stall. Stock stall is going to be different so be ready for it.

One thing I will say is that the stock transmission cooler is...okay...for stock. Once you start beefing up the transmission, and especially the TC, you're going to be making a lot more heat. From my own experience, the stock cooler couldn't cut it. I installed a larger, more efficient unit from Derale, and that was much happiness. Ford not including a transmission temp gauge stock was a mistake IMO.

One more thing: fluid. I've tried the gambit, and the stock-spec Ford fluid (Mercon V) is still the best IMO. I ran Royal Purple for a while, but it seemed overly sensitive to temp and didn't seem to hold under all conditions...plus that darn purple dye makes it annoying.

 

[JC SSP]

Heat is the number one killer of transmission. A bigger and more efficient cooler is a must on any hi-perf set up.

 

[RielyHodge]

So the built transmissions can handle the power, but I need to cool them properly?

 

[RielyHodge]

I installed a larger, more efficient unit from Derale, and that was much happiness.

Did you use the one designed for the 11-14 mustangs, or did they stop making them for the 05-09 mustangs after you got one?

 

[Autokyrios]

Did you use the one designed for the 11-14 mustangs, or did they stop making them for the 05-09 mustangs after you got one?

Neither. I run one of their universal remote cooler. I don't know that they make any Mustang-specific coolers.

 

[RielyHodge]

They have them for 11-14 mustangs, I was thinking that maybe you got one and got it to fit on an 05-09 Mustang. Did you get the -8AN line or the -6AN line one, and how much did it cost, I can't find the price. Also, where did you end up putting it?

 

[05stroker]

Once you move past 550 rear wheel horsepower these transmissions will not live no matter what you do to them. 700 hp will take it out. Do some searching on here. We already tried this way back in the day they will not live.