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MT-82 transmission leak

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So, I purchased the Boss, got it home, and drove is a couple of times before I noticed a small half dollar sized puddle where the car had been parked in the garage. Before I drove it the next time, I looked underneath to see where the leak was coming from. Directly under the transmission. I put it up on my lift and found this:

ER4h0YG.jpg

I looked back at the photos that I had the boutique dealer send me of the bottom of the car (before purchase) and I can see the outline of the leak on the heat sink vanes fed by the scoop taken at an angle away from the transmission itself. Not taken directly under it. I don't see any drips in the photo either. I would have bought the car regardless but still...

Anyway, given my research on TMO, this is a stuck open vent valve assembly on the top of the transmission requiring removal of the transmission in order to fix it. I believe Ford has a redesigned vent valve assembly. Can anyone confirm that? P/N?

This next part is going to sound familiar. So, since everything is stock from the flywheel to the driveshaft, I think I will save some more money and replace the flywheel, clutch, shifter, and driveshaft all at once when the transmission is out.

There are a lot of good parts suggestions on TMO for others who have followed this path. I will think it over and post up my plan here.

The planned use for the Boss is HPDE, back roads fun, car shows, and daily driver reliability so I will be picking parts with that use in mind. This car will not be a full time dedicated track car. I anticipate 2-3 track days a year.

In the meantime, I checked the fluid level (with a hook shaped twisted paper towel - that hole is so small even my pinky finger couldn't get in) and found it to be approximately 1" lower than the fill hole bottom. I will be topping it off until I can pull the transmission for repair and upgrades.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Hi LS291:

Yes, it is most likely the vent valve at the top of the MT82 transmission. Mine had the same problem during my first year or so of ownership and was repaired under warranty by my Ford Dealer.

There are several good clutch/flywheel options out there to choose from and I would recommend going with a lightened steel flywheel for your application. The Pilot bearing is replaced with the new flywheel but while you're there consider replacing the hydraulic T/O bearing as well. Remember to order new bolts for the flywheel and pressure plate. Some are TTY bolts. Note: I also installed the FRPP stainless steel clutch fluid line when the transmission was out, but that's just me as I'm not a fan of plastic tubing for a hydraulic pressure line. I can say that I do like the feel of the clutch pedal better with this upgrade.

When you add transmission oil, the fill point is 1/2" below the side fill hole. Then consider changing the transmission oil when you reinstall it after the clutch replacement. Ford does have a TSB on MT82 fluid to assist with shifting in colder climates. I had this TSB performed and the new fluid with additive did improve shifting in 50 degree weather. I park her for the winter months so no real experience with shifting in colder weather.

You'll find this is a great forum for finding technical information for your Boss that applies to your particular driving/operating needs.

Good luck with your repairs, and keep us posted.
302 Hi Pro
 
Most likely that's the cause. Or the fluid was changed and overfilled.
 
Great suggestions 302 Hi Pro. I will be sure to get the TOB, bolts, and SST line. I am not a fan of plastic pressure lines either. I didn't know that was the original material.

I already have the XT-11-QDC fluid and XL-18 additive from the TSB. I have not shifted the car beyond ~6500 rpm at this point knowing the issues with the factory hardware. Thus far I have had no shifting problems. I am being careful with it until the upgrades. However, I did test drive a different Boss 302 where I got the 2nd to 3rd gate lockout at about 6500 rpm or so.

I will get it topped off per your suggestion and post up my results after some driving.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
I few other items to consider.

Additive. Ford recommended and then soon after removed the recommendations for the KL-18 additive. Apparently there is a compatibility issue with the additive. I added and then dumped the fluid with the additive. I use Redline MTL in the trans, no complaints.

I see from your photo the stock shifter is still there. A MGW shifter is a good idea. The difference in feel and performance is very noticeable. I eliminate about 90% of my lockouts with the MGW shifter. The Clutch is the best fix.

One cure for the breather issue is to extend the breather with a rubber line to just behind the engine. The fluid drains back down the line. I believe there a re a few posts here describing the process. This would be a good alternative if you cant source upgrade parts from Ford.

Like 302 stated, flywheel and clutch bolts should be replaced not reused. they are TTY and or factory equipped with Loctite. ARP has a flywheel bolt kit. I believe ford is the best source for the flywheel bolts.

The leak is a good sign that your new/old car has bee driven gently. Otherwise, the leak would have been addressed earlier under warranty.

Welcome to the site and the club!!

PS. Not a better bunch of guys to give advice on how to spend your money than right here. LOL.
 
680
215
I'm actually getter to ready to pull the trigger on the Mcleod RXT. If you decide to go this route, Mcleod sells pressure plate bolts that are made by ARP. ARP does not sell them but they only cost $18 or so dollars for them. Part number is 1505. I would also recommend the aluminum flywheel as well. This set up will probably be the last clutch you ever put in the car.
 
1,022
99
Exp. Type
HPDE
Exp. Level
10-20 Years
Texas
I got the RST and love it...just don't buy the McLeod clutch line. Mine ended up leaking. I've replaced the o-ring but may just put the stock one back on. The stock line is just fine in my opinion and more reliable.
 
While you are in there....
I noticed a large improvement in shifting after installing the MGW (first gen), urethane engine mounts, and the Whiteline transmission mount insert. Once the engine and trans are held much more firmly to the chassis you don't get a significant misalignment of the shifter and trans, in my opinion. I have not installed my Blowfish shifter bracket yet but I have had 0 issues on the street and track so far. But I don't drive as fast as many of the other guys here yet :).

Also: I know many have, but I don't think it's a good idea to install just the trans mount insert by itself. It seems to me that you will put more stress on the trans mount if the engine mounts are stock since they are pretty squishy. So you have all the torque of the engine squishing the engine mounts and turning that trans mount into a stiff fulcrum. Plus I like the slight engine vibration I get with the stiff mounts. It makes the car feel more raw/connected but the NVH is negligible in my opinion.
 
I topped off the trans and drove it to work yesterday. No issues. The more I become acquainted with the car the more the stock shifter feels like a disconnected noodle. My 95 GT has a G-force T5 with a Steeda Tri-axe shifter and I can rip gears at the rev limiter no problem. The remote shifter really feels strange.

TMS Boss - are saying not to add the XL-18? Ford pulled the recommendation? If that is true, this is the first I have ran across this.

Sent from my XT1254 using Tapatalk
 

TMSBOSS

Spending my pension on car parts and track fees.
7,530
5,247
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
TMS Boss - are saying not to add the XL-18? Ford pulled the recommendation? If that is true, this is the first I have ran across this.

[/quote]

Yes. Ben Calmer, huge MT-82 guy posted this info on Facebook. Apparently there is a unfavorable reaction between the additive and stock fluid. Ford no longer recommends. I dumped the additive and added redline without issues

Yea, stock shifter with remote mount is a limp noodle on a good day. I ordered my MGW shifter before I had 500 miles on my Boss. I added one to my daughters 2013 Mustang also. Your T-5 has the shifter integrated to the housing, right?
 
TMSBOSS said:
TMS Boss - are saying not to add the XL-18? Ford pulled the recommendation? If that is true, this is the first I have ran across this.



Yes. Ben Calmer, huge MT-82 guy posted this info on Facebook. Apparently there is a unfavorable reaction between the additive and stock fluid. Ford no longer recommends. I dumped the additive and added redline without issues

Yea, stock shifter with remote mount is a limp noodle on a good day. I ordered my MGW shifter before I had 500 miles on my Boss. I added one to my daughters 2013 Mustang also. Your T-5 has the shifter integrated to the housing, right?

Ok, thanks for the feedback. Since I already have the Ford XT-11-QDC fluid, I will use it for now, less the XL-18 additive. As I recall, it was for cold weather shifting improvement only. Since I don't drive my Mustangs after December 1, I'm not going to worry about it. If I have issues down the road, I will look to an aftermarket transmission fluid at that time.

Yes, the T5 has the shifter mounted rigidly to the tailshaft of the transmission.
 
I checked under the Boss today. Correction: 1" diameter oil leak directly under the transmission with a shiny reflection of my previous clean up.

Not as bad as I thought.

Still, I am making my list of upgrades from the threads on this site. I'll post it up here once I get it figured out.
 
Well, I finally got around to upgrading a couple of key parts of my Boss and decided to check the source of this leak at the same time. (I added an X-spec MGW and the Ford Racing aluminum drive shaft - man that stock 2-piece DS is ugly!).

Installing the shifter requires dropping the trans crossmember for easy access. Since I had the driveshaft out as well (and exhaust disconnected), the trans dipped down until the engine was resting on the firewall (on an old towel of course). That left me plenty of room to get my hands up around the trans and check things with an inspection mirror.

Seems like the leak is not actually coming from the vent near the front of the trans. It is actually coming from something around where the shifter connection is on the top near the back. Unfortunately, there was no way for me to tell exactly where given that the fluid was all over the top. So, I wiped the whole thing down top and bottom and put it back together. I will give it some time and have another look in the spring when I change my oil.
 
Well, I finally got around to upgrading a couple of key parts of my Boss and decided to check the source of this leak at the same time. (I added an X-spec MGW and the Ford Racing aluminum drive shaft - man that stock 2-piece DS is ugly!).

Installing the shifter requires dropping the trans crossmember for easy access. Since I had the driveshaft out as well (and exhaust disconnected), the trans dipped down until the engine was resting on the firewall (on an old towel of course). That left me plenty of room to get my hands up around the trans and check things with an inspection mirror.

Seems like the leak is not actually coming from the vent near the front of the trans. It is actually coming from something around where the shifter connection is on the top near the back. Unfortunately, there was no way for me to tell exactly where given that the fluid was all over the top. So, I wiped the whole thing down top and bottom and put it back together. I will give it some time and have another look in the spring when I change my oil.

LS291, I'm very interested if you found the location and source of the leak you are describing since I have the same type of leak. It doesn't show up on the garage floor after each drive, just occasionally. The location of the spots on the floor is right under where the shifter sits. What is most annoying is the smell that I get sitting at a stoplight with the windows down after the car is fully warmed up. It is definitely a hot oil smell. But is the oil getting hot from the tranny itself or is it dripping on the exhaust?
 
Tackman,
I have not located the source of the leak. It was right on the seam on the back of the transmission right above where the MGW shifter locates to the circular mounting ears. After cleaning it up and putting a couple hundred miles on it, I have it back up on the lift for a spring change and there was only a single drip in the original location (no evidence on the floor). I chalk that up to residual run down from the seam and other areas too small for my fingers to fit in. Until I know otherwise, I will continue to drive it. If I figure it out, I'll post up here.

Sent from my XT1254 using Tapatalk
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,425
8,354
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Congrats on acquiring a very rare LS ( I believe there were even fewer in Silver than done in School Bus Yellow in 2013 ?) and you are in the right part of the Country to enjoy the Boss! With Pittsburgh International and Pocono in your State, and New Jersey Motorsports Park and Watkins Glen decent drives away, you have plenty of places to go play. Yeh, I know there are other tracks reasonably close, depending on where you are in PA., but don't want to fill up another paragraph, ha.

TMS stated it perfectly and glad to see you got an MGW short throw shift kit. George has had numerous Mustangs, from GTs to GT 350s , and plenty of Boss models ( including a Boss S) , and his passion for the Mustang is unmistakable. He builds the absolute best system and that could be discreetly verified even by some fanboys at Ford.

Do continue to keep us posted on your upgrades and send VoodooBoss a conversation note to see if he as any TMO T Shirts still for sale --- easy way to recognize your fellow Forum Trackrats when at road courses around the US.
 
It could simply be mine was over filled from the factory. Time will tell.

Sent from my XT1254 using Tapatalk
Thanks LS291,
I didn't notice the drips on the garage floor or the smell until after I had changed the transmission oil. I am hoping that I just overfilled or didn't tighten the fill plug enough. I hope to get it on a lift soon to see if there are drips at the fill plug or any other oil tracks.
 
24
47
Exp. Type
HPDE
Exp. Level
5-10 Years
San Diego
LS291,

....."replace the flywheel, clutch, shifter, and driveshaft all at once when the transmission is out.......so I will be picking parts with that use in mind. This car will not be a full time dedicated track car. I anticipate 2-3 track days a year."

Similar goals to your, my Boss is a daily driver built for safety & reliability while attending 3-5 HPDE event a year. My drive train is comprised of the Exedy Racing Stage 1 Organic Clutch kit (07807csc) w/the Exedy Aluminum Flywheel (EF502A); the MGW Short Throw Shifter; Shelby ISO Clutch Resevoir (384320); and Whiteline Transmission Mount Bushing Insert (KDT928).

By the way, I will be attending the Boss 302 Reunion/HPDE event 30 Aug-1 Sept @ Pitt Raceway...do you plan on attending?:

https://www.facebook.com/events/pit...ce-complex/boss-reunion-2019/258732998303728/

A new driveshaft is on my wish list, let me know what you decide on.

Good luck with 291, Dennis DiLucente
 

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