Installed a Tremec Magnum XL in my S550

[Norm Peterson]

Took on a new project and thought I’d share it. Never thought I’d go this route but but just saying that doesn’t really surprise me.

This is what I ended up buying and most of this comes in a kit which is the route I went:

Tremec Magnum XL transmission (duh)
First gear choice of 2.66 and opted for the 5th and 6th OD gears of the 2.97 trans which gives me in order of 1st to 6th, 2.66/1.78/1.30/1.00/.80/.63

Quick Time steel sfi bell housing

QA1 carbon fiber driveshaft with sfi (upgrade)

Bowler all-in-one harness for electronic connections

Rest of the kit included fluids, transmission mount, cross brace and mounting hardware

Also added the MGW shifter since I really appreciated what it did for the MT82


I cannot say enough about the transmission. I absolutely LOVE the gears I chose granted I’m in the break in phase and not shifting over 4000 rpm for the most part but again, this is how the car will be driven most of the time. First and second gear are so much more useful and enjoyable to use. Fourth gear (1.30) in the MT82 was one of my most favorite gears to play in and also was a factor in choosing the magnum gear selection I did because third gear in this set is also 1.30 which made it perfect. 4th is now the 1:1 gear which I like and the two OD gears are gapped perfectly unlike our 5th to 6th is in the 15-17 MT82. I will say it is weird downshifting to 1st gear around corners in residential/commercial zones but it’s easy, called for and works like any other gear you’d be used to using normally. Hell, I’m still learning what gear to be in based on muscle memory of where the shifter used to be. I really couldn’t be happier with how this all works together and with the stock 3:73.

It's encouraging to have read just this far - your review is pretty much what I'd expected, but it's better and means more when it comes unsolicited.

I'm looking to do the same swap with the same gearing for my 4.6L S197. 4 to 5 in that transmission is just as bad as 5 to 6 in the original MT82 gearset, and there are other times where I'd like to see 1st be worth a few more mph.

Looks like there's way more in here than I'll be able to take in in a single sitting, some of which I still expect to get some benefit from.

Thanks.

Norm

Sponsored

 

[Ashtar]

New vibration after install...

The answer… Check the driveline angle. Too much angle can cause vibration. Fix? Shim the top of the transmission.


Now the story…


I recently had the swap from the MT82 transmission to the Tremec T56 Magnum XL in my 2015 Ford Mustang GT. I did not do the labor. I paid to have it done. What was changed - the transmission, Mcloud RTX clutch, and a Chromoly drive shaft. The flywheel already installed in the car is a Mcloud Steel Lightweight flywheel. Yes, the flywheel was resurfaced.


The issues that were experienced are as follows. They needed to make room for the lockout solenoid, figure out where to hook up the 12v for the solenoid, bleeding the clutch and driveshaft alignment. This post has addressed most of the issues. I took the time to make the transmission shop aware of this post and they were able to avoid the lockout solenoid issue. I still need to figure out where to hook up the 12v. They ran into the issue with bleeding the clutch.


The other issue that I ran into was what seemed like a driveshaft vibration. And it only seemed to happen at higher speeds, 80 mph. Once I felt the vibration, I could recognize it, because I knew what it might feel like at around 70ish. I then talked to the company that I had bought the parts from, AMP Performance Parts. Those people there know what they are doin’! Chris has answered so many questions from me AND the company that put in the transmission. Anyway, they made a few suggestions, like disconnect the drive shaft and rotate it out 180 degrees. This new driveshaft only had 4 bolts instead of the 6 that the OEM shaft had. He also suggested, selecting one of the other two mounting points. I did these steps, and still no change. So I was going to have the rear end changed to 4.11 gears from the 3.55’s that were already in it. And the company that did the shaft also did rear ends. They, too, were recommended by AMP. So I talked with them and set up a time for me to come down to get the gears swapped out and have them look at the shaft as well. Well, they ran into shipping issues with the gears. Things were pushed back. They did not get a chance to look at the shaft and they did not get a chance to run the car up to speed and check for the vibration. They did get a chance to take it out but they were “not able to access the freeway because it was a parking lot.”


One of the things I ran into was this - my day job. I’m a computer guy, and I work for Go Daddy. In my younger years, I used to turn wrenches many a day. I’ve pulled engines and replaced clutches a lot! Hated my mom’s AMC Hornet’s clutch. Even went on to work on F-15’s as a Jet Engine Mechanic. It has been years, might even say a few decades, since I’ve seriously turned some wrenches. I kept hearing “Well ya know, when you start putting in some aftermarket hardware, you’re going to run into some extra sounds.”


/rant on

Now if ya can… imagine Lewis Black, if you can. I’m going to tone things down a bit, but needless to say I was pretty pissed. I know it’s going to make more noise. I have poly inserts in the rear, the springs have all been changed to lower and stiffen the suspension. I’m now running 20’s for the rims, and a lower profile tire. And I’ve got a twin turbo kit by Hellion! Let’s not forget the exhaust has been changed as well. Yes, I know my car is going to whine a bit, it’s going to vibrate just a bit more as well. And some strange wonderful sounds are going to be happening as I accelerate onto the freeway. I get it, my car is not OEM anymore.

/rant off


What I needed to do is find someone whose daily job is dealing with these types of cars. I did - Black Market Racing. They took the time to listen to my issue. They took the car out for a drive, up to speed. I got a call back from them saying “Yes, there is a vibration and I would not drive the car down the track as it is.” They took the driveshaft back to the company that made it and had them test it again. The driveshaft company did, and did not find anything wrong with it. During this test they took it up to 3300 rpm. BMR called the company back and asked them, “can you take it to a higher speed?” The company in question then asked for the car back. BMR took the car back to the company. The driveshaft company had found that the rear of the transmission was sitting too high, thus creating a more acute angle that was allowed. This was causing the vibration. They placed a few shims at the top of the transmission to adjust the angle.


No more vibrations… Thank you, Black Market Racing! Thank you, AMP Performance Parts!

 

[aleccesarenriquez]

They just shimmed the cross member? What about the shifter mount; it doesn’t sit too low now?

 

[db252]

The shims won’t make a dramatic difference to the shifter height. A little bit goes a long way for pinion angle though. Shims are added, if necessary, usually between the transmission and cross member to raise it or to lower the angle, add shims between the cross member and the body. Proper pinion angle is very important and can really help with vibration that might otherwise be thought of as a driveshaft out of balance.

 

[Ashtar]

@db252 Any thoughts on shimming the rear end/frame instead of the transmission?

 

[aleccesarenriquez]

@db252 Any thoughts on shimming the rear end/frame instead of the transmission?

Do you know what size shims they used? Should they be rubber, polyurethane, aluminum?

If you have any pics, I'd be interested in seeing them

 

[Ashtar]

@db252 Not sure what this means... If you could explain any of it... It would be helpful.

 

[db252]

@db252 Any thoughts on shimming the rear end/frame instead of the transmission?

Not sure I would do that. Seems as there would be too many other things affected by doing that. No real reason not to do it at the trans.

Do you know what size shims they used? Should they be rubber, polyurethane, aluminum?

If you have any pics, I'd be interested in seeing them

Stainless washers are what I’ve used in the past. You don’t want anything that will compress. My setup is not shimmed at all.

@db252 Not sure what this means... If you could explain any of it... It would be helpful.

Looks like they are using 6 pieces of flat bar to shim in an orientation I’m unaware of unless seeing it in person. The bolts are most likely extended over what was provided to accommodate the height change.

 

[Ashtar]

@db252 and anyone else. What driveshaft are you using? Also it sounds like I am one of the few that has to shim. IE: carbon fiber, steel or chromoly?

 

[db252]

I’m using a QA1 driveshaft which you can see in the first post. It’s costly but wouldn’t use any other personally. Had one with my mt82 long before as well. Not sayin other driveshaft brands or materials don’t work; just seem to be more problematic.

 

[RubberFeet]

db252 - Not forced induction, but same trans/DS as you. Just received my Lund tune. No time ti deal with it now.
Car is running quite rough. Will report when I get everything working. The only thing I can think of is the shorter DS geometry demands more exact rotational centering back to the diff. You give me encouragement that you didn't need shimming. More later. I agree that shimming the diff ass'y is a very bad idea. As the flight instructor said. "one mistake compounds to 10 in short order".

 

[Ashtar]

I’m using a QA1 driveshaft which you can see in the first post. It’s costly but wouldn’t use any other personally. Had one with my mt82 long before as well. Not sayin other driveshaft brands or materials don’t work; just seem to be more problematic.

I have already been told a couple times that a carbon fiber driveshaft might be better.

 

[AramEJ]

Hi Guys,first excuse my language, am new in all this, I have 2016 mustang GT PP with phase2 Roush tun by Roush, I swapped the trany like more that year ago mt82 to t56, am having issue not only with cross control not working but form some reason am going into a limp mode as I have been told
( whoever tun and adjust t56 gear ratio ) that it is a transfer case torque limitation!! Am basically when I push hard car going on limp mode( car not allowing me to keep going) then I go back to neutral and I try again and it works it is doing off and on, also what is the pulse count that you just using in the 3-1 harness? Do I need to adjust VSS in the ECU? I appreciate you help and reply.

 

[db252]

Hi Guys,first excuse my language, am new in all this, I have 2016 mustang GT PP with phase2 Roush tun by Roush, I swapped the trany like more that year ago mt82 to t56, am having issue not only with cross control not working but form some reason am going into a limp mode as I have been told
( whoever tun and adjust t56 gear ratio ) that it is a transfer case torque limitation!! Am basically when I push hard car going on limp mode( car not allowing me to keep going) then I go back to neutral and I try again and it works it is doing off and on, also what is the pulse count that you just using in the 3-1 harness? Do I need to adjust VSS in the ECU? I appreciate you help and reply.

Got your pm but figured I'd respond here.

Cruise control won't work until your tuner puts in correct ratios for all gears. First and foremost, if it hasn't been done yet, you'll need to convert the pulse count from 12 (T56) to 36 (MT82) in the 3-1 harness so that the PCM can read it. Limp mode is probably happening from the 3-1 harness not programmed properly or the tune itself but start with the harness. We don't have a transfer case but that's probably just a lost in translation thing.

 

[AramEJ]

Gear ratio was already being set in the tun, Cruise control will work if I set count pulse to 12 in the 3-1 and in the VSS inside the ECU to 12 as well, also the speed in the 3-1 will match my speedometer, if I set to 36 in 3-1 cruise control won’t work (knowing the original VSS was set at 34) and my speed will be way off about 40to50 mile.

Sponsored