Plan for Correcting the Drivetrain Sins of the S550 GT

[IamCDNJosh]

So I realize that all of these points may have been individually covered in other posts, but I wanted to have others with experience poke holes in my plan here for my 2015 GT PP1.

First I'm not really interested in selling this car, it was something I bought after leaving an unhappy marriage and I didn't have anyone to tell me "no". This car represents not only my freedom but my decision to be happy in my life. With that out of the way, I've been VERY interested in the approach that Ford has taken with the new Mach 1 in installing the Tremec 3160 as well as having a differential cooler. Getting a Mach 1 really isn't an option, I could afford it but I'm not going to pay 30+K for a car that's similar to what I have now. Lastly, I tend to avoid the aftermarket when at all possible, I'd call my style OEM+ which is why I've stuck largely with FP, Roush & RTR for both my GT and F150.

My car is primarily a GT car, I'm not trying to keep the miles down plus I want to use it for a few track days per year. For power mods I'm not going to add anything additional, I've got a Roush PP1 (Intake & ECU flash that is octane adaptive for any of those rural gas stations that may not have premium) along with the FP Sport exhaust with the GT350 rear valance (more on that in a bit). For suspension I've kept my PP1 suspension stock other than getting the FP X-springs which gives me all the components from the Street Handling Pack. No plans on FI as the compression & cooling is not ideal for track use, that and with power at that level I'd want some kind of DCT anyways.

So that being said, I'm looking to do a drivetrain overhaul that will give me a Tremec 3160 like experience as well as not having to worry about my differential temps at the track. So that being said, below are my plans and I'd like to have some input here from those that have experience. As I have a second vehicle to drive (F150) downtime is not a concern as well as I can do most of the work myself as I've been wrenching on cars since I was a teenager (almost 40 now)

1. Transmission Rebuild - We all know the MT-82 has some serious design flaws, while my transmission hasn't failed it grinds while its cold as well as being extremely notchy. I've toyed with going for a 3160 but it sounds like I'd have to load some kind of custom tune to make it work so this may be a non starter as I'm not interested in an e-mail tune. The other Tremec options are off the table but the ratio's aren't ideal for an N/A setup like mine with a 3.73 rear. So that brings me to an aftermarket solution. I'm looking at removing my working MT-82 and sending it to Calimer Performance to do a Stage 1 rebuild. Remember here I'm likely only going to be pushing 470ish to the crank. The clutch line would be replaced by the FP upgraded version M-7512-B. Flywheel would be replaced by the Ford performance version M-6375-M50 and would love suggestions for a clutch (please keep in mind my power output, I don't need some crazy clutch rated for 1000hp).

2. Shifter - This is quick, but I do have a Ford Performance unit sitting in my garage, I haven't installed it because I haven't quite decided which way I'm going.

3. Remote Mount Issue - Now I've had the infamous 3rd gear lockout, to which I ordered the whiteline transmission bushing and sawed off the middle section to reduce NVH in the vehicle as this is a drivers car my new wife will ride in, not a racecar. Beyond that I may have to go to the aftermarket here as there isn't a factory option and get a blowfish bracket as this will also be compatible with the FP short shifter. Sorry not interested in a Barton/Steeda unit.

4. Differential - I've seen some of the workarounds for trying to have extended tracktimes with the differential but they all come across as bandaids. Now I know that there is a unit from FTB which seems to be perfectly capable. Again I want to go OEM here if I can which brings me to what I'd really like to do to address this issue.

I'm looking at purchasing the GT350 rear closeout panel as the GT350 valence on my car is the OEM piece. Closeout Panel

I would also like to purchase the GT350 rear differential cooler to go along with it. GT350 Cooler

I realize that this is more expensive than the FTB cooler, but again I'm trying to stay OEM wherever possible and I'm going to be keeping this car in my collection for a long time.

5. Transmission Cooling - For transmission cooling at track days I was looking to install the FP air scoop and it will be only installed for track days and otherwise removed when street driven (my car will be trailered to the track). FP Transmission Air Scoop


So that's it, sorry for the long winded post but like I said I'm wanting to correct the sins of the S550 GT without having to purchase a new Mach1. Any thoughts, suggestions or debate would be appreciated. Budget isn't much of an issue, so again I'm not interested in cheap band-aids but rather I want to do this right without adding NVH or negatively affecting drivability.

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[MRGTX]

All of the stuff you've mentioned here sounds worthwhile, assuming your applications will demand it.

It sounds like you have experienced the third gear lockout but maybe only once? If you're going to rebuild the whole transmission, it might be a good idea to change the shifter first and see if you need to actually rebuild it.

Sure, the trans has some flaws but I'm convinced that most of these flaws are the expectations set by the reputation on forums like this one. I am on my second MT82 and I still really like it. It doesn't feel as good to shift as my dad's GT500 (with the T6060) but it's still fun for rowing the gears.

As for the cooling, these are always good upgraded but have you been monitoring temps up to this point? What tells you that you need this?

 

[IamCDNJosh]

I have experienced 3rd gear lockout and the whiteline bushing seemed to help with that particular issue. My issue is that the shifting action is still notchy, and will grind when cold. I know that I can do things like changing the fluid but this doesn't solve for poor quality. I'd rather pull a healthy transmission and have it corrected then add the FP cooler scoop for some insurance when I'm working it hard on a lapping day. For the rear differential cooling, I want to address this because it appears to be the Achilles heel on these cars for doing a complete lapping day as well. I've toyed with purchasing a Mach-1 but I believe this route will be MUCH more economical if done right.

I don't have any hard data other than seeing forum posts and reading about differential overheating issues. I very much value reliability and want a car that will survive multiple 20 minute sessions during the day. FYI, I'm not exactly new to track days but I am new to them in cars.

Prior to having children, this was my track day machine of choice.

 

[shogun32]

CBR F4 is a good steed.

If you're gonna pull and ship the trans, I would do at least a level2 build on it. And put in a 2-plate clutch. Also you HAVE to get the Steeda shifter bushing (U-shaped thingy $70) if you don't have it.

I'm curious why you haven't mentioned any of the chassis/IRS fixes.

 

[IamCDNJosh]

Understood on the shifter bushing, like I said I will go aftermarket when needed. Great question on the IRS lockout, and it is something that I have considered. First and foremost this is a street car, my wife already complains about the Recaro's and I'm hesitant to add anything to the vehicle which will transmit any additional NVH. My mustang will never be a dedicated track car as I just like driving too much. It's also why I've opted for the street handling pack vs the track handling pack components. I don't want a car that I would hate taking on a road-trip.

If I were to address the IRS I'd probably get a subframe with the solid bushings pre-pressed in which would have to come out to install the differential cooler anyways.

IRS Subframe

Also since I have zero interest in drag racing I also question if I would see much benefit to the subframe upgrade.

 

[shogun32]

It's also why I've opted for the street handling pack

I missed that. Do NOT get those street dampers. They are the same as the PP1 and rubbish. Track pack or Bilstein.

Solid bushings in the IRS (if you mean Delrin or 6061) is not advised if you are concerned about noise. Get the Whiteline 'drop-in' or 'press-in' kits instead. The backend of the car isn't connected to the front if you're using factory setup. Fix the 4 bushings and throw on the Steeda IRS brace and you get rid of the hinge in the back. You can then feel/read what the hell the back of the car is doing.

 

[IamCDNJosh]

I did not purchase the street handling pack, only the X-springs. The rest of the components from the street handling pack came with my car since it's a PP1.

 

[HeelToeHero]

Have you had the differential temp warning come on? Lots of people don't have an issue with it (myself I've run 6 events and never had it come on. Additionally my temp sticker on the cover hasn't gotten very warm either).

You can spend a lot of money unnecessarily by reading stuff posted here.

 

[v guy]

Modern Driveline has a complete Tremec T56 conversion kit for about $6,000

 

[IamCDNJosh]

Have you had the differential temp warning come on? Lots of people don't have an issue with it (myself I've run 6 events and never had it come on. Additionally my temp sticker on the cover hasn't gotten very warm either).

You can spend a lot of money unnecessarily by reading stuff posted here.

I have a 2015 which I believe did not come with a temp sensor. I guess just go with some diff fluid that's resistant to higher temps for track days and hope for the best....

 

[IamCDNJosh]

Wife said I could either go through with this project or do an overlanding setup on my F150 (rack, rooftop tent etc). I'm more interested in overlanding, so I'll be doing a trans and diff fluid change and calling it good.

 

[IamCDNJosh]

Forgot to mention I'm going to do the Steeda IRS braces as well. Thanks to all who responded!

 

[Elp_jc]

I'm hesitant to add anything to the vehicle which will transmit any additional NVH.

I was on the same boat, so just added the front (2-point) and rear Steeda sub-frame braces, and they didn't add any NVH... but they made a remarkable difference, especially the rear one, and they're fully reversible, with no need for re-alignment. So mission accomplished. Any other mods, like adding solid bushings, etc., would definitely add at least 1 of the 3 NVH elements, if not all 3. Good luck.

 

[ice445]

I'd skip rebuilding the MT-82 and just swap in a Magnum XL. With a 2015 you won't run into any tune related issues or anything like that.

 

[IamCDNJosh]

Not a fan of the ratios in the magnum XL. The 15-17 ratios are very good for an N/A setup especially with a 3.73 rear. I'll have it rebuilt when it fails.

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