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Boss Transmission/Clutch Issues Poll

Have you experienced any of the issues below?

  • Have you experienced shifting lock out upshifting in any gear?

    Votes: 146 57.9%
  • Have you experienced any shifting lock out downshifting in any gear?

    Votes: 56 22.2%
  • Have you experienced any grinding when shifting the car cold?

    Votes: 97 38.5%
  • Have you experienced any grinding when shifting the car hot?

    Votes: 59 23.4%
  • Have you experienced the clutch pedal partially sticking while shifting above 6,500 RPM's?

    Votes: 68 27.0%
  • Have you experienced the clutch pedal sticking to the floor while shifting above 6,500 RPM's?

    Votes: 45 17.9%
  • Have you experienced any of the above while using TracKeY?

    Votes: 75 29.8%
  • I have not had any shifting issues.

    Votes: 42 16.7%
  • I have not had any clutch issues.

    Votes: 63 25.0%
  • Have you documented any above issues with your dealer?

    Votes: 37 14.7%

  • Total voters
    252
I never thought much of this transmission and clutch combo. It got to the point that I was unable to shift into 3rd and 6th under normal conditions without grinding the gears. I just took it to Ford and it took them all of one day to tell me they are going to replace the entire transmission and clutch assembly.
 
teamconn said:
I never thought much of this transmission and clutch combo. It got to the point that I was unable to shift into 3rd and 6th under normal conditions without grinding the gears. I just took it to Ford and it took them all of one day to tell me they are going to replace the entire transmission and clutch assembly.
You were lucky, congratulations. Are you driving your Boss on track?
 
No. Its completely stock street car. I also have a 2014 Shelby. After I got the Shelby, and compared the 2 clutch actions, although I know they are different set ups it however made me realize that there was something not right with the Boss. As soon as 3rd became to grind, it was enough for me to take it in. The transmission is on order. I need to get a little more info as to what made them determine it needed replacing and what will be different with the new tranny.
 

TMSBOSS

Spending my pension on car parts and track fees.
6,284
3,314
Exp. Type
HPDE
Exp. Level
5-10 Years
Illinois
You may want to consider swapping the clutch while you have the trans out.

I have read where a few guys were lucky enough to buy the new clutch and the dealer swapped the clutch when the trans was out at little to no cost for labor.

I thought my clutch was not a problem. I recently swapped the stock unit for a RST. Huge difference.

I believe the stock clutch puts more strain on the syncros. They then wear causing the grinding sound you mentioned.

This may be a good opportunity to change the clutch and Not pay for the labor.
 

Mad Hatter

Gotta go Faster
4,001
2,504
Santiago, Chile
Build date found on inside your drivers door: 04/27/12
Do you have skip shift disabled (2011/2012 owners only) YES
Have you replaced your transmission fluid? If yes what did you install? YES REDLINE and ROYAL PURPLE
Have you replaced your brake fluid? If yes what did you install? YES CASTROL SRF
Have you installed an aftermarket shifter? YEs MGW
Have you installed an aftermarket shifter bracket? YES BLOWFISH
Have you installed an aftermarket clutch line? YES
Have you installed an aftermarket clutch? If yes what did you install? YES SPEC 1
Have you tracked your car? Track, autocross or strip? TRACK
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. None completed
Have you removed your clutch assist spring? YES
Do you own a Boss or GT? Boss
 

DEye

You can't get there from here...
Build date found on inside your drivers door: TBD
Do you have skip shift disabled (2011/2012 owners only) No
Have you replaced your transmission fluid? No
Have you replaced your brake fluid? No
Have you installed an aftermarket shifter? No
Have you installed an aftermarket shifter bracket? No
Have you installed an aftermarket clutch line? No
Have you installed an aftermarket clutch? No
Have you tracked your car? Track, autocross
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. No
Have you removed your clutch assist spring? No
Do you own a Boss or GT? 2012 Boss
 
No problems to date @ 12400 miles
Build date found on inside your drivers door: 4/2011
Do you have skip shift disabled (2011/2012 owners only) No
Have you replaced your transmission fluid? Yes- per Ford TSB
Have you replaced your brake fluid? Yes Dot 4 ATE
Have you installed an aftermarket shifter? No
Have you installed an aftermarket shifter bracket? yes
Have you installed an aftermarket clutch line? No But Do have stand alone clutch fluid resv.
Have you installed an aftermarket clutch? No
Have you tracked your car? Track, Yes autocross No
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. No
Have you removed your clutch assist spring? yes
Do you own a Boss or GT? 2012 Boss Boss
 
Build date found on inside your drivers door:
Do you have skip shift disabled (2011/2012 owners only)? Yes, No or NA
Have you replaced your transmission fluid? If yes what did you install? Has the updated FLUID.
Have you replaced your brake fluid? If yes what did you install? no
Have you installed an aftermarket shifter? MGW
Have you installed an aftermarket shifter bracket? Steeda Tranny mount stiffener
Have you installed an aftermarket clutch line? Not yet
Have you installed an aftermarket clutch? If yes what did you install? Ram, but had to modify to fit late prod. Boss
Have you tracked your car? Track, autocross or strip? no street only!
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. Trans rebuild, 2,3,4, gears, 3 syncro assys., forks, sliders, rails, and part of the case. The problem with the trannys is the nylon slider that goes on the end of the shift fork, It is what moves the syncro hub back and forth. Mine were all broken or worn down to nothing. Need to be made out of bronze. Anybody with a lathe and mill could make them easily, I only have the mill, no lathe.
Have you removed your clutch assist spring? no
Do you own a Boss or GT? 13 Boss.
 

drano38

Wayne
1,130
318
Build date found on inside your drivers door: May 2011
Do you have skip shift disabled (2011/2012 owners only)? No
Have you replaced your transmission fluid? If yes what did you install? Yes, Redline MTL, yearly
Have you replaced your brake fluid? If yes what did you install? ATE Yellow/Blue
Have you installed an aftermarket shifter? no
Have you installed an aftermarket shifter bracket? Blowfish Racing
Have you installed an aftermarket clutch line? no
Have you installed an aftermarket clutch? no
Have you tracked your car? Track, autocross or strip? Yes, track, ~ 3 weekends a year
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. none
Have you removed your clutch assist spring? no
Do you own a Boss or GT? 12 Boss.

Overall I'm having pretty good luck with the clutch. I generally shift ~ 6,500-7,000 RPM. A few times on a track weekend on a 3 to 4 shift, it doesn't seem to move completely into 4th gear, but in reality it did--just gives a bit of resistance.
I'm thinking about installing a McLeod RST, but all parts and install are ~$1,800. So I'm struggling with dropping that kind of coin when I'm upgrading my house with windows/steel siding this summer.
 
170
219
Exp. Type
HPDE
Exp. Level
3-5 Years
Irvine, CA
Build date found on inside your drivers door: 07/11
Do you have skip shift disabled (2011/2012 owners only) No
Have you replaced your transmission fluid? If yes what did you install? No
Have you replaced your brake fluid? If yes what did you install? Yes, ATE DOT4
Have you installed an aftermarket shifter? No
Have you installed an aftermarket shifter bracket? No
Have you installed an aftermarket clutch line? No
Have you installed an aftermarket clutch? If yes what did you install? No
Have you tracked your car? Track, autocross or strip? Track (x4) and Autox (x2)
If you've had any warranty work completed related to your clutch or transmission please describe as briefly as possible. No
Have you removed your clutch assist spring? No
Do you own a Boss or GT? Boss

Notes:
Since the poll only let me vote once for one option and some of my issues/solutions need explaining:
-I always use the TracKey.
-I have experienced upshift lockout at high RPM (especially 2-3) and downshift lockout if I am trying to rush the shift (5-4 typically).
-I also have a really notchy 1-2 upshift especially when cold, feels like there is something in the way (the skip shift mechanism?).
-5th gear synchros are definitely going, possibly even 6th gear and some others too (grinding when I rush a shift).
-My clutch pedal has stuck partially to the floor after a high RPM shift, especially if I then skip some gears (i.e. 3-5 or 6) but always returns shortly (a second or 2).
-Following my first track day the transmission will now refuse 1st gear engagement from a stop about 1/3 times. No grinding initially, the shifter just physically stops about halfway and will not go all the way into the fully engaged position so the gear does not engage completely. If I release the clutch at that point it grinds and pops out. Sometimes I can just push harder or retry the engagement with the clutch still depressed and it forces into gear, but usually it requires a few double clutches until 1st gear will engage completely. This is my most concerning issue right now since...
-I have been able to almost entirely eliminate my lockouts by changing my shift technique as recommended by Ben Calimer and others on multiple forums. The idea is to let the springs naturally guide the shifter into place and just push the shifter up into 3rd or 5th rather than forcing it and missing the gate and getting locked out. If I try to rush the shift too much I can still experience the lockout, but that's usually user error. I'm not saying that the lockout issue is acceptable for a car of this caliber, but I wanted to share my 2 cents that don't think the clutch is the only issue/solution, a lot of it has to due with the physical shift mechanism/mount and technique.
-I took my car to the dealer and asked about the clutch sticking, high RPM lockout, and 1st gear engagement issues. They said they could not reproduce the clutch sticking or high RPM lockout and did not have time to ride with me while I drove to show them, but I did show them the 1st gear engagement issues and their guess was that it is a bad 1st gear synchro (really?), but they wouldn't know for sure until they drop the tranny which I did not want to do at that point.

I do have an extended aftermarket warranty but want to try to nail down the issues and causes/solutions before going through with any transmission/clutch repairs/replacements.
I hope my input helps someone, and I will try to update the forum (not necessarily this thread) if I solve any of the issues.
 
The problem with the stock clutch is you’re probably doing damage to the trans and dont know it. The MT-82 has a glass jaw. The fixes for a street/track driven car are:

Aftermarket dual disc clutch. I recommend the McLeod RST not the RXT.
Remove the clutch spring.
Install a MGW shifter or Blowfish Racing shifter bracket or both.
 
SaveTheManuals, my clutch had the same issue of 1st not fully engaging sometimes, Thought it was my synchros or clutch, tried the MGW shifter but still got locked out of 1st. So I was reading of what might cause the issue, either a faulty slave cylinder or air in the clutch line. I decided to try to bleed the clutch by trying a technique i read on a different forum. I lifted the driver side with a jack and began pumping the pedal slowly, after a couple pumps, i began to hear a hissing (hydraulic) sound similar when your bleeding your brakes. Kept on pumping the clutch pedal until i could feel it getting stiffer and the sound went away. Popped the master cylinder cap and could feel some pressure released. Took it for a test drive and haven't been locked out of 1st since.
 
Last edited:
Sad to say but it seems the Boss was never built to maintain track duty. Sure, it had the platform to get there but the rest was up to you. The GT350 was much more capable, but that's even having issues. I don't track my Boss and tho I drive it hard at times, I've never had any problems with it..........knock on wood! Strongest part of the Boss was that beefed up Roadrunner engine but that even failed for some folks.
 
The problem with the stock clutch is you’re probably doing damage to the trans and dont know it. The MT-82 has a glass jaw. The fixes for a street/track driven car are:

Aftermarket dual disc clutch. I recommend the McLeod RST not the RXT.
Remove the clutch spring.
Install a MGW shifter or Blowfish Racing shifter bracket or both.
Any clutch will alleviate the issue, no need for a dual disc i would think. But the dual disc is a small performance and shifting improvement over most singles.
 
592
167
Unfortunately, I can't agree that "any" clutch will fix it because I first went with a Spec Stage 1 clutch and alloy flywheel and it did exactly nothing to help the high rpm lockouts. The RST finally cured it 100%.
 
I also don't think any clutch will work. Plenty of examples of single disc clutches not getting it done. While the McLeod is certainly not the only clutch that will work it's a know fix. The Exedy single disc clutches Kohr Motorsports sells seem to work. Don't confuse what works in a race car, 302S for example, with what works in the Boss or GT. Different trans. The McLeod engineers explained it to me that the centrifugal force at high RPM's is part of the cause of the stock clutch not fully disengaging. The McLeod RST and RXT have had good success.
 
Last edited:
This is good info as I am about to replace the clutch on my 13 Boss with 13K miles. I get locked out of 5th on the track and have decided enough is enough. So why the RST over the RXT? I also considered an Exedy from Kohr but couldn't decide on a single or twin disc. Exedy isn't cheap but after buying a lightweight flywheel the McCloud isn't either. So my question......go with a twin disc over single?
 

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