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Has anyone done the Magnum XL swap and regretted it?

15
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
Calimer is a drag racer so are most of the guys over at Mustang 6g. Road course puts more stress on the trans since you have to shift up and down. The down shifting is probably harder on the trans than the upshift. Combine the constant high rpm shifting with 20-30 sessions or more on track and heat is a real factor that isn't an issue for high horsepower cars on a drag strip.
Yah I totally get the heat from RPM, upshifting and especially downshifting. If not done properly, (I double clutch on the way down) downshifting really beats up the synchros and generates a LOT of additional heat in a localized area. I've not had an MT82 apart yet, but I assume they have some type of clutch facing on the blocker rings, which makes them grippy and fast shifting, but probably doesn't survive the rigors of road course use well, hence the comments I've seen other members make about dog rings LOL.

I'm just trying to satisfy curiosity here and wondering if I should get a hold of a core and start looking into it myself. There are TONs of these transmissions out there, and if there was a real solution that was cost competitive with the Tremec, I'd think it would save lots of headaches. I get what Calimer is saying when he refuses to stand behind an installed trans. In his mind if it's got 6 forward gears and one backwards gear and it spins over on the bench it's a good unit. The issue is it's not that simple in real life, and admittedly road racing is the harshest environment and the customers are low volume compared to all the mouth breathers that drag race. ;) So I'm sure when a road race guy starts having failures he doesn't have a good answer, and it's not his bread and butter anyway...
 

JDee

Ancient Racer
1,516
1,540
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
I had my MT82 rebuilt last year with the Syncrotech carbon kit. After a full year it's still working fine. It's hard to justify the cost of a Tremec kit, it costs out at well over $10K up here. That's about 5 MT82 rebuilds.

Very few trans guys will touch this trans where I live, fortunately there's one guy who likes to do this kind of thing, he's really a Tremec guy but likes a challenge. All the shafts, bearings were OK, but the syncros and all the shifting parts were done. Also had a couple of gears chipped that had to be replaced, third and fourth gears really take a beating.

Perhaps the biggest key to making the MT82 live is a proper racing clutch, Exedy Hyper Single was my choice. The stock clutch is not suitable for road course work at all. You won't hear the damage it's doing under full throttle, but rest assured it's junking your trans. That should be the first thing you replace in a Mustang for track work.
 
15
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
I had my MT82 rebuilt last year with the Syncrotech carbon kit. After a full year it's still working fine. It's hard to justify the cost of a Tremec kit, it costs out at well over $10K up here. That's about 5 MT82 rebuilds.

Very few trans guys will touch this trans where I live, fortunately there's one guy who likes to do this kind of thing, he's really a Tremec guy but likes a challenge. All the shafts, bearings were OK, but the syncros and all the shifting parts were done. Also had a couple of gears chipped that had to be replaced, third and fourth gears really take a beating.

Perhaps the biggest key to making the MT82 live is a proper racing clutch, Exedy Hyper Single was my choice. The stock clutch is not suitable for road course work at all. You won't hear the damage it's doing under full throttle, but rest assured it's junking your trans. That should be the first thing you replace in a Mustang for track work.
Thanks for your input, it helps me understand what's really failing in these units, it appears my suspicions were correct in your situation.

I also hear everyone say the stock clutch is a problem as well and if I'm honest I'm having trouble visualizing what the problem is there. Is there some sort of centrifugal apply or drag at high RPM and it's not disengaging all the way? Is the friction disc super heavy or has a huge MOI that makes the input shaft hard to accelerate or decelerate? Something that beats the trans up under heavy use that you don't see just putting around on the street? My trans with an MGW shifter works great with the stock clutch, but I pulled the 3-4 in a damn hurry next to a concrete barrier last week with the window down and I heard the trans clash as it went into 4th. Not something you can feel or hear in the car, but I heard it against the concrete barrier with the window down.

Thanks for all the spoon feed and sharing of experience here. I'm still new to the S550 platform, and new to Fords in general as I've always been a GM guy till a few years ago. Plus I'm an engineer and I like to geek out on these details and understand the actual root cause of what's going on. I like to document the actual issues here vs just perpetuation the here say that's all over other forums and facebook...
 

Mad Hatter

Gotta go Faster
4,671
3,388
Santiago, Chile
To be fair to the MT82, the fellow who is repairing my box also does the Porsche gt4 units... He says he sees the same failures with them and as frequent, particularly now that they are all running slicks. He did improve the life of these EXPENSIVE units by switching to Motul 75/140 racing Gear oil, wants to try the same oil in my rebuilt unit. Very curious to see what that does...... probably will be terrible when cold.
 

JDee

Ancient Racer
1,516
1,540
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
It may sound counterintuitive, but my trans guy said you want thinner oil, not thicker. The syncros don't work well with thick oil and that leads to all the problems we see. The last Ford recommendation I saw for this trans is for their DCTF. I am using Motul DCTF and so far no problems and the trans shifts better than it ever has.
But that's a bit of a religious topic, sort of like engine oil, so that's all I'm going to say about it.
Cooling is also key, if you're not running a trans cooler you're going to eat these things alive.
 
15
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
It may sound counterintuitive, but my trans guy said you want thinner oil, not thicker. The syncros don't work well with thick oil and that leads to all the problems we see. The last Ford recommendation I saw for this trans is for their DCTF. I am using Motul DCTF and so far no problems and the trans shifts better than it ever has.
But that's a bit of a religious topic, sort of like engine oil, so that's all I'm going to say about it.
Cooling is also key, if you're not running a trans cooler you're going to eat these things alive.
I concur with your trans guy. I can see why some would want thick oil given the assumption that it thins out from the heat, but modern oils are pretty stable. Also, you want that oil to fling off the hot parts and cooler oil to come in contact. Thick oil will just hang on and you won't get the same cooling effect.
 
436
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Thanks for your input, it helps me understand what's really failing in these units, it appears my suspicions were correct in your situation.

I also hear everyone say the stock clutch is a problem as well and if I'm honest I'm having trouble visualizing what the problem is there. Is there some sort of centrifugal apply or drag at high RPM and it's not disengaging all the way? Is the friction disc super heavy or has a huge MOI that makes the input shaft hard to accelerate or decelerate? Something that beats the trans up under heavy use that you don't see just putting around on the street? My trans with an MGW shifter works great with the stock clutch, but I pulled the 3-4 in a damn hurry next to a concrete barrier last week with the window down and I heard the trans clash as it went into 4th. Not something you can feel or hear in the car, but I heard it against the concrete barrier with the window down.

Thanks for all the spoon feed and sharing of experience here. I'm still new to the S550 platform, and new to Fords in general as I've always been a GM guy till a few years ago. Plus I'm an engineer and I like to geek out on these details and understand the actual root cause of what's going on. I like to document the actual issues here vs just perpetuation the here say that's all over other forums and facebook...
A little background. My car is a dual use S197, street and HPDE. I don't race it and have never had slicks or a tire wider than 285 mm. From what I have seen, the stock clutch and MT82 is adequate if you stay below 450 rwhp and 7,000 rpm rev limiter. My factory set up made it over 93k miles and around 40 track days. I put on a ported Boss intake and throttle body and it made 447 rwhp and the rev limiter was increased to 7,400 rpm after tuning. It drove fine on the street, but had clutch problems the first track session. I stopped driving and put it on the trailer to avoid trans damage due to the clutch issues. It still drove fine on the street. I pulled the trans over the winter for the clutch swap and sent it to Calimer for a stage 2 build to ward off future problems. No one in my local area wanted to work on it. After tear down they said there wasn't any noticeable damage in my MT82 and recommended a stage 1 or 2 build for my horsepower and usage. I asked about stage 3 and was told it was not necessary for my use. When 4th gear blew apart just after break in I was then told I needed a stage 3 with an upgraded 26 spline input shaft for $3,700 plus freight.

It looks like the stage 1 or 2 are no better than stock. The stage 3 has some stronger gears, but still uses some of the stock gears and synchronizers. The Tremec Magnum XL swap kit is around $3,795 plus some wiring. You also need a new drive shaft. I was going to have to upgrade to 26 spline clutch either way so I am calling that a wash. At least now I have a new transmission that is easier to find someone to work on or is replaceable with another new transmission if the need arises. I am not stuck with the few guys around that will work on the MT82.
 

Mad Hatter

Gotta go Faster
4,671
3,388
Santiago, Chile
Would agree to tall of that.. A XL is on my Xmas list. About the oil. the idea the mechanic has is that you need a thicker oil to slow down the gears a little when the clutch is engaged allowing the syncros to work better...... The GT4 drivers all say it improved the useful life of the transmissions. :idontknow:
 
162
152
Thanks for your input, it helps me understand what's really failing in these units, it appears my suspicions were correct in your situation.

I also hear everyone say the stock clutch is a problem as well and if I'm honest I'm having trouble visualizing what the problem is there. Is there some sort of centrifugal apply or drag at high RPM and it's not disengaging all the way? Is the friction disc super heavy or has a huge MOI that makes the input shaft hard to accelerate or decelerate? Something that beats the trans up under heavy use that you don't see just putting around on the street? My trans with an MGW shifter works great with the stock clutch, but I pulled the 3-4 in a damn hurry next to a concrete barrier last week with the window down and I heard the trans clash as it went into 4th. Not something you can feel or hear in the car, but I heard it against the concrete barrier with the window down.

Thanks for all the spoon feed and sharing of experience here. I'm still new to the S550 platform, and new to Fords in general as I've always been a GM guy till a few years ago. Plus I'm an engineer and I like to geek out on these details and understand the actual root cause of what's going on. I like to document the actual issues here vs just perpetuation the here say that's all over other forums and facebook...
My understanding is the diaphragm springs in the stock clutch and pressure plate aren't strong enough to fully disengage the clutch at high rpms. If you think of how a diaphragm spring works, the high rpms create a centrifugal force that makes it harder for the spring to disengage the pressure plate. A higher rated clutch with a stronger diaphragm spring fixes the problem.

If everything shifts fine at 6500 but you are locked out at 7000, this is likely your problem. If it shifts poorly or is grinding at lower rpm, your problem is likely elsewhere.
 

Mad Hatter

Gotta go Faster
4,671
3,388
Santiago, Chile
True... and the one leads to the other... Poor clutch leads to lock out, that leads to grinding gears and that leads to bits of metal in the transmission.......

Then again nearly 590 hp to the flywheel and high rpm shifts are going to kill most gear boxes eventually. Look at the Cayman GT4 transmissions for example, they seem to loose third gear often... and thats an actual gear failure.
 
15
15
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
My understanding is the diaphragm springs in the stock clutch and pressure plate aren't strong enough to fully disengage the clutch at high rpms. If you think of how a diaphragm spring works, the high rpms create a centrifugal force that makes it harder for the spring to disengage the pressure plate. A higher rated clutch with a stronger diaphragm spring fixes the problem.

If everything shifts fine at 6500 but you are locked out at 7000, this is likely your problem. If it shifts poorly or is grinding at lower rpm, your problem is likely elsewhere.
This is the first time I've ever heard anyone articulate what the issue may be. Makes sense. I've never experienced lockout, but I can get the trans to clash if I upshift really fast at high rpm and sometimes it will do it heel toe-ing on the way down as well. Maybe I need to be planning a new clutch at some point even just as a preventative measure.
 

Mad Hatter

Gotta go Faster
4,671
3,388
Santiago, Chile
You can remove the helper spring on the clutch which improves the clutch's ability to disengage as well (much heavier clutch feel). I have had mine out for ages and it did stop the clutch pedal from staying on the floor when at high rpm. BUT would strongly recommend upgrading the clutch any how.
 
436
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I agree that it really isn't necessary after test driving the car yesterday. I was told that it was necessary and have the control box and wiring harness already. My car is still a street car, so I am going to use it since I have it. It is mostly wired in. I just need to locate a switched 12v source to tap into for the hot. I'll let you know how much difference it makes once I finish it up.
I finished wiring in the reverse lock out solenoid last week. There is an unused plug in the console that is used for the gear selection indicator on automatic transmission cars that has a switched hot that is unused on the manual transmission cars. I used it to feed the control box. I am in agreement with @Fabman that it is not necessary. If my car was a race car I would have left it out. My car is a street/HPDE car and it is a nice addition for a car that uses reverses a fair amount around town. The control box activates a solenoid at speeds under 10 miles per hour which makes it effortless to shift into reverse at low speeds, but makes it difficult at higher speeds to avoid accidentally hitting reverse instead of 5th at speed.
 
436
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
My Steeda drive shaft loop doesn't fit with the Magnum XL. Which driveshaft loop are others using after the swap?
 

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