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Mach 1 Track Build & Dark Horse Overheating + Trans Failures – Need Proven Cooling Setup

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Hmm that’s disappointing. No wonder they don’t last. What does opg mustang sell? what is synchro max is that atf? I usually deal with truck manuals and jeeps they all seem to use gear oil or maybe i have t been paying attention. I sure hope the jerico trans uses something thicker lol
 
Because it is not compatible with the syncronizers in the 3160. Mercon LV is the correct fluid for GT350/Bullit/Mach 1 and Dark Horse 3160 transmissions.
@steveespo curious if you would say the same thing about an MT-82 with carbon synchronizers? I know that Tremec likes ATF for the friction profile for the synchros -- but Tremec has also run different types of synchros too and they've always recommended ATF...

The only difference I found that might be significant to lubrication between the MT-82 and various Tremecs is that the MT-82 is entirely reliant on splash oiling whereas most of the Tremecs also pump the oil around through some kind of lubrication pathways. I read that too thick a fluid can be a problem for some of these Tremec systems -- synchronizers aside...

What do you think? Maybe I'm remembering wrong but I thought you ran BG in your MT-82 with carbon synchros?
 
I put BG into my MT82. Haven’t dealt there the tremec yet as it’s brand new. I know guys here put a fluid pump on the mt82 by hosing input and drain plug and a diff fluid pump and cooler. The tremec appears to hold twice the fluid which is good
 
I put BG into my MT82. Haven’t dealt there the tremec yet as it’s brand new. I know guys here put a fluid pump on the mt82 by hosing input and drain plug and a diff fluid pump and cooler. The tremec appears to hold twice the fluid which is good
I've got a weirdo MT-82. Tremec gear profiles and carbon synchros built by a Tremec builder. Builder specifically said Dex3 ATF only. I stuck with that for a while, ran fine -- then -- after a while -- like a real genius I couldn't resist questioning my builder. I started wondering why ATF? Carbon synchros or not... I started looking at everything and I only found that expert opinions are all over the place. Calimer uses carbon synchros and he recommends thick MTF. Lashbrook uses carbon synchros and they recommended Motorcraft DCTF (which was recommended by Ford for OEM brass synchronizers). Ford itself originally recommended thick MTF back in 2011. Tick Performance strictly recommends ATF for their Tremecs. Several opinions on TMO from people with real experience, but Mad Hatter (the MT-82 king) uses thick gear oil if I remember right, some guys like BG and redline. For Tremecs most people stick with ATF but some don't... Lately I've been thinking that fluid choice is less important than it seems, but the things that matter seem to be the friction profile -- it has to work with the synchros, and the viscosity has to match the transmission AND the driving style... Thing is though that when I ask, most fluid companies are saying that their fluid is fine for carbon synchros... Pick your poison I guess?

steveespo's comment just made me a bit concerned... wondering if he has some knowledge on the topic.

BTW, I picked BG specifically because it seems to have been designed to mimic ATF. Same viscosity profile and from what I can tell it was originally designed for (and tested with) older Tremecs with carbon synchros... Shifted much smoother with the change (less stiff/notchy), but does that mean it's better for longevity? I dunno.
 
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So do the race cars have trans issues?? Same 3160 and fluid??
The transmissions are pretty durable considering the abuse thrown at them by the drivers. And yes we run the same Motorcraft Mercon LV. People have to remember that GT4 race transmissions at the Pro level are refreshed pretty much every event, with less power run through them. We usually get 3-4 weekends before the shifting starts to show issues. Rebuilds are done at Liberty Gear and the cost is pretty reasonable unless catastrophic damage occurs like a broken main shaft or gear. Typically it is just sychro replacement 2-5 and bearings. We have seen some infant failures but it is usually due to an incorrect installation that causes a partial release bearing situation which then wears the synchros or chips a gear.
 
I've got a weirdo MT-82. Tremec gear profiles and carbon synchros built by a Tremec builder. Builder specifically said Dex3 ATF only. I stuck with that for a while, ran fine -- then -- after a while -- like a real genius I couldn't resist questioning my builder. I started wondering why ATF? Carbon synchros or not... I started looking at everything and I only found that expert opinions are all over the place. Calimer uses carbon synchros and he recommends thick MTF. Lashbrook uses carbon synchros and they recommended Motorcraft DCTF (which was recommended by Ford for OEM brass synchronizers). Ford itself originally recommended thick MTF back in 2011. Tick Performance strictly recommends ATF for their Tremecs. Several opinions on TMO from people with real experience, but Mad Hatter (the MT-82 king) uses thick gear oil if I remember right, some guys like BG and redline. For Tremecs most people stick with ATF but some don't... Lately I've been thinking that fluid choice is less important than it seems, but the things that matter seem to be the friction profile -- it has to work with the synchros, and the viscosity has to match the transmission AND the driving style... Thing is though that when I ask, most fluid companies are saying that their fluid is fine for carbon synchros... Pick your poison I guess?

steveespo's comment just made me a bit concerned... wondering if he has some knowledge on the topic.

BTW, I picked BG specifically because it seems to have been designed to mimic ATF. Same viscosity profile and from what I can tell it was originally designed for (and tested with) older Tremecs with carbon synchros... Shifted much smoother with the change (less stiff/notchy), but does that mean it's better for longevity? I dunno.
I have run BG in all of my MT-82 transmissions. We were told specifically by Ford and Tremec to run Mercon LV spec fluids in the 3160.
 
What actually died on the them?? Was it just syncros and 2, 3rd and 5th gears? Maybe you should look at a built tremec then. When we put a oil cooler and pump setup with a temp gauge on the previous semi stock MT82s the transmission temperatures were hotter then the engine, frequently went to 300 F. When we switched to the Calimer stage 3 with billet gears (semi square, noisy), the temps went down to below 200F and 150 with the pump going. It well worth going to 26 spline as well.
 
I don't know if anyone has made the A10 transmission work well for track duty. It's going to take a fair amount of coolers and venting to get things under control.

I believe I have, atleast for casual HPDE track days, and with minimal coolers, venting or airflow. Flyhalf has gone through multiple 10r80's, but he competes at a very high level, is a winning champion and has broken records. I believe at advanced level track driver or below, the transmission will hold up just fine with my modification.

My solution was bypassing/deleting the 210F internal transmission thermostat, and installing a 160F external thermostat along the cooler lines. I wouldn't consider it an easy or simple mod, but I posted about my project and outcome here: https://www.mustang6g.com/forums/threads/10r80-custom-thermostatic-valve-and-cooler-lines.217478/
 
I believe I have, atleast for casual HPDE track days, and with minimal coolers, venting or airflow. Flyhalf has gone through multiple 10r80's, but he competes at a very high level, is a winning champion and has broken records. I believe at advanced level track driver or below, the transmission will hold up just fine with my modification.

My solution was bypassing/deleting the 210F internal transmission thermostat, and installing a 160F external thermostat along the cooler lines. I wouldn't consider it an easy or simple mod, but I posted about my project and outcome here: https://www.mustang6g.com/forums/threads/10r80-custom-thermostatic-valve-and-cooler-lines.217478/
Ok, so step 1, you installed a larger external transmission cooler (Mishimoto). Still could not do a 20 minute session.
Odd. The PP1 in 2018 has a very small cooler for the transmission, so this should have helped.

So step 2 you installed a 160° thermostat (compared to the 190° stock unit).

LOL, I love the schematics!

1785069466513.png



Seriously, that is one of the best threads I have read in a long time. You even included details others would have skipped, such as your trepidation at lifting the car all four corners off the ground in your garage. There is enough detail there to probably duplicate this if others wanted to do it.

Thank you for sharing it.

But to be honest, the removal of the valve body and all those little pieces may have scared me off from this mod if my trans ever starts to overheat . . .

Still a maximum of 200° on track?

So you think it is ok for winter driving on the street, to the grocery store?

Have you bypassed the stock water to transmission fluid exchanger that actually warms the transmission oil with hot engine coolant?
 
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I missed this the first time through his first post, so if anybody else is reading the other thread he linked, here is how to get the OEM thermostat out and replaced with a bypass. He put this in his post, but it is easy to miss (it is a large post).

 
Ok, so step 1, you installed a larger external transmission cooler (Mishimoto). Still could not do a 20 minute session.
Odd. The PP1 in 2018 has a very small cooler for the transmission, so this should have helped.
The mishi cooler actually did help a bit, but not nearly enough. It probably bought me an extra 5 minutes(lap or two) at intermediate pace/level driver? I only bought it because it was the most OEM style option with metal cooler lines that are directly plug and play. I also planned on installing it myself, but ended up just paying the dealer to install it for me. It's hard to directly compare mishi benefits because my skill/pace was growing at this time, it was summer time with high ambients, and I was short shifting out of an abundance of caution after my first 10r80 died. Looking back now, I would have rather done my project with the OEM cooler to leave more real estate and airflow to the radiator, OR gone with a superior cooler than Mishi. Hindsight is 20/20 but imo mishimoto is low tier quality and performance.

So step 2 you installed a 160° thermostat (compared to the 190° stock unit).
Yes, and my decision to go with 160F version instead of the 180F or 140F version was due to balance/compromise on a street/track car. I wanted just enough extra heat tolerance and margin before overheating, while being as close to OEM temps as possible. I had spoken with Alessandro(FlyHalf) a few times about potential solutions, and he suggested 140F version. Our understanding is you want over 140F for fluid to expand, lube properly and to create appropriate line pressure - its for transmission performance and longevity. I had originally wanted a 170F option, since 180F would have been too high and close to OEM. After seeing where 160 lands me, I guess I was right that 170F would have been a touch more balanced for OEM like operating temperatures.

LOL, I love the schematics!
LOL me too. I could have made it prettier but I was in a "get it done" over "make it pretty" mood when starting the project. I had already researched and thought through this project for years... it was time to just get it done no matter what! Plus I like the scrappy vibe instead of alwasy striving for a perfectionist look - just felt right to break away for once.

Seriously, that is one of the best threads I have read in a long time. You even included details others would have skipped, such as your trepidation at lifting the car all four corners off the ground in your garage. There is enough detail there to probably duplicate this if others wanted to do it.

Thank you for sharing it.
Thank you - that means alot. I wanted to share as much details as possible because as a noob myself, I would get lost when others share projects and I am not as familiar with the lingo or the mechanical operations. I wanted others who are not as mechanically experienced to know that a total noob could do this, and that they could too. And that I'm here to help if they decide to undertake it too.

But to be honest, the removal of the valve body and all those little pieces may have scared me off from this mod if my trans ever starts to overheat . . .
Yes, I felt the same, but looking back now, I could probably do it again in less than a weekend. The hardest part and delay was making mistakes, being unfamiliar with what is proper procedure or not, and waiting for new parts...also lamenting over decisions and details instead of just doing it. A 10r80 is not an inexpensive way to try my hand at wrenching!

If you decide you wish to give it a go, DM me and we can have a call to start. I can walk/facetime you through it all, before, during and after the project.

Still a maximum of 200° on track?
Yes! 200F max, sits around 170F street driving in moderate california weather. It does take longer to get up to temp if getting on the highway - gets to temp quickly, almost same as OEM, if city stop and go driving.
So you think it is ok for winter driving on the street, to the grocery store?
Yes, depending on "winter" temperatures. The improved racing external thermostat I use provides like 10% flow at all times, so colder ambient will take longer to warm up because it is still being constantly cooled with 10% flow. So with this mod, no matter which temperature thermo you pick, it will always take longer than OEM to heat up - plus I have the thermo placed many feet down the lines, so the fluid is cooling off away/out of the transmission while it passes through the lines before it hits the thermo. I can't comment on below 40F, but at or above that it will reach temp within 15-20 mins of highway driving, maybe 10 mins of city driving with frequent stop and go.

Have you bypassed the stock water to transmission fluid exchanger that actually warms the transmission oil with hot engine coolant?
There is no water to transmission fluid exchange that I know of. Transmission fluid goes straight to and from the transmission cooler.
 
There is no water to transmission fluid exchange that I know of. Transmission fluid goes straight to and from the transmission cooler
Sorry, this is an S650 thing. see the 7A095B item in the diagram below. It hangs out just under the front area of the transmission. I did not realize it was not on the S550.

So I wonder if an S650 owner can something like you have done and still have a quick warm up from the tranny fluid to coolant heat exchanger. The engine would warm up the transmission. Or would this defeat the purpose? 🤔

I don't know if this coolant to fluid heat exchanger shuts off after a certain temperature or whether it just keeps dumping 200°+ temps into the transmission fluid.

1785157380318.png


The 7A095A, in front of the radiator, is the auxiliary transmission fluid cooler on the performance pack and Dark Horse models (inc. the Dark Horse manual transmission models, too, but not the regular GT manual transmission models).
 
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7A095B is that aluminum looking long box to the right of the photo. Ignore the red circle, which is the tranny fluid dip stick stuck right by the catalytic converter because Ford wants you to burn your hand.

1785158017751.png
 

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