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krisk

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In the week leading up to and including the July 4 celebration of 250 years of independence in our great nation, I went on a road trip totaling more than 2,600 miles attending three HPDE track events with Chin over the course of eight days. I had a great time despite losing one full day due to a mechanical problem with my car. More on that below.

Track 1 - Virginia International Raceway. This was my first time at VIR (as well as the other two tracks), and I had a great time. We stayed in the Pit Lane Suites, which was extremely convenient in being able to walk from our room to the paddock. The track was great, as expected, and the weather turned out well although it was a little warm. My 2024 Mustang did great on track although the coolant was low on the morning of the second day. It had been low before I left home and I had it pressure tested at a local shop, but they found no leaks. Since I still found no leaks I assumed it was just an issue with the coolant venting from the overflow when hot.

Track 2 - Watkins Glen. Watkins Glen was my favorite track of the three on the trip. The weather was good, but it was pretty warm for what I would expect in New York. On the morning of the first day my coolant was again low, but still no noticeable leaks. The car ran great, but the coolant level was below the minimum line once the car cooled down between each session. I was adding 8-12 ounces of water between sessions, and I began seeing a little puddle of coolant/water under the car. At the end of the first day I completed an oil change in the garage and noticed the residue of coolant around the transmission.

Breakdown - Upon further inspection, I was able to determine that the nipple on the transmission heat exchanger was leaking. It wasn't coming from the hose or any fitting; rather it appeared to be coming directly out of the aluminum, so I assumed there was a tiny crack. After many calls to dealerships around the country, I sourced a heat exchanger in stock at an Alabama dealer, and had them overnight me the part to our next track location. $70 part plus $220 overnight shipping.

Unfortunately, I lost my second scheduled track day at Watkins Glen because I didn’t want to risk having the heat exchanger spring an even bigger leak and dump coolant on the track or damage the car. We packed up and headed down to Summit Point, WV. The part arrived right at noon the following day, and I was able to get permission to use a church’s parking lot to do the replacement. Of course this was probably the hottest day of the year. The temperature hit 99 degrees while I’m laying on the asphalt doing the replacement, which also involves filling and checking the transmission fluid. It was not a fun experience, but a little over seven hours later I finished and confirmed I had no leaks.

Track 3 - Summit Point. With the car fixed, I was able to run at Summit Point for two full days. Of the three tracks I visited, it was my least favorite, but it was still a great time. The weather was good up until the the 4:30pm happy hour when they had to shut down the track for lightning on the first day.

Considering the length of the trip and having six track days scheduled in an eight day period, I think having a single breakdown and repair wasn’t too bad. My wife and I really enjoyed the trip and will likely try to do a similar one next summer.

The photos below in order at VIR, Summit Point, our matching tow rig, then my parking lot repair. There was no photographer for day 1 at Watkins Glen, so no photos from that track, which was disappointing.

S650 Mustang 8 Days - 3 Tracks - 1 Breakdown IMG_9907


S650 Mustang 8 Days - 3 Tracks - 1 Breakdown R6M28099


S650 Mustang 8 Days - 3 Tracks - 1 Breakdown IMG_6294


S650 Mustang 8 Days - 3 Tracks - 1 Breakdown IMG_6314
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Junkyard Dog

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Wow, you really upgraded your trailer!

What a great story, especially changing the transmission heat exchanger over 7 hours in 99 degree heat in a church parking lot (which required that pain in the butt transmission fill procedure).

So it was leaking coolant . . . meaning hot coolant is in the transmission heat exchanger? How does that help cool off the transmission fluid?


EDIT: Ok, so it's true. The engine coolant is used to warm up the transmission fluid.

Then we are trying to cool it off, presumably with this same hot engine coolant still present. How much heat exchanging can be going on with 200°+ coolant in a liquid to liquid cooler?

It almost sounds like the cure to 10R80 heat is just to run an outside cooler, not tied to engine coolant, maybe even remove this liquid to liquid one. That does not sound like it would do any cooling at all.

Is that the only cooler for the transmission fluid?
 

BimmerDriver

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Glad you had fun! VIR is my home track and WG is on my bucket list. SP is OK, but kind of ... well, you know. I went there once, and that was enough. LOL

Since you're in GA I'm sure that you've done RA and Roebling as well. If not, you should.

I presume that your car is still under warranty, but since that's not typically a stocked part, I guess you didn't have much of an option, unfortunately.

I was thinking of doing what you did (road trip involving multiple tracks) but never got beyond the dreaming stage. Kudos and thanks for sharing!
 

DH401

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My father my two brothers and I were also there at VIR as well as Watkins Glen. We didn’t go to summit point, I haven’t looked into getting any of the photos yet I will have to do that. I remember seeing your car there. The 4 cars we had brought were a 2024 992 GT3RS, 2024 Ford Mustang Dark Horse (Blue Ember), and two 2024 Mustang Gt’s (Black and Rapid Red). It was also our first time to VIR but we have been to Watkins Glen before. These are the only two photos that I took myself at the track

S650 Mustang 8 Days - 3 Tracks - 1 Breakdown IMG_8605


S650 Mustang 8 Days - 3 Tracks - 1 Breakdown IMG_8606
 
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krisk

krisk

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Wow, you really upgraded your trailer!

What a great story, especially changing the transmission heat exchanger over 7 hours in 99 degree heat in a church parking lot (which required that pain in the butt transmission fill procedure).

So it was leaking coolant . . . meaning hot coolant is in the transmission heat exchanger? How does that help cool off the transmission fluid?


EDIT: Ok, so it's true. The engine coolant is used to warm up the transmission fluid.

Then we are trying to cool it off, presumably with this same hot engine coolant still present. How much heat exchanging can be going on with 200°+ coolant in a liquid to liquid cooler?

It almost sounds like the cure to 10R80 heat is just to run an outside cooler, not tied to engine coolant, maybe even remove this liquid to liquid one. That does not sound like it would do any cooling at all.

Is that the only cooler for the transmission fluid?
You are correct on the heat exchanger. It has two separate passages; one for the engine coolant and one for the transmission fluid. Mine was leaking from the coolant nipple. The coolant heats up a lot more quickly since it is running through the engine, so when the transmission is still cold the coolant warms up the transmission fluid. Once the transmission fluid is hotter than the coolant, the coolant then pulls the heat from the transmission fluid by running through the exchanger. So it is both a cooler and a warmer depending on the temperature of each fluid.

All Mustang automatic transmissions have the heat exchanger. On ones without a separate cooler, the transmission fluid just cycles through the heat exchanger then back into the transmission. The Dark Horse and GT Performance Package have a separate transmission cooler mounted behind the radiator. For these cars the fluid cycles through the heat exchanger, then up to the cooler via a thermal bypass valve which opens once the transmission fluid reaches a certain temperature. So the transmission cooler only receives the fluid once the transmission heats up, but it constantly cycles through the heat exchanger.
 
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krisk

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Glad you had fun! VIR is my home track and WG is on my bucket list. SP is OK, but kind of ... well, you know. I went there once, and that was enough. LOL

Since you're in GA I'm sure that you've done RA and Roebling as well. If not, you should.

I presume that your car is still under warranty, but since that's not typically a stocked part, I guess you didn't have much of an option, unfortunately.

I was thinking of doing what you did (road trip involving multiple tracks) but never got beyond the dreaming stage. Kudos and thanks for sharing!
I agree on the tracks. VIR was a really nice complex and track. SP was fun, but not a destination track; I would go back, but only if it was in a situation like this where it is part of a trip somewhere else. WG was great, and I am definitely planning to go back. It's over 16 hours from my house, so it will likely be another road trip with multiple tracks the next time I go.

The car is under warranty and it would have been covered. However, it was worth the $300 plus a day of aggravation so I wouldn't miss out on two more track days. Sourcing the cooler was tough and took both my son and wife calling around the country for a couple hours before finding a dealer who had one and would overnight it. The poor parts guy in Alabama felt bad for charging so much for shipping, and we had to keep telling him yes we were sure we wanted it overnight and the fee was fine. LOL

Edit: I have done several events at both Road Atlanta and Roebling as well as Barber, AMP, The FIRM and Sebring. I'm about halfway between Road Atlanta and Sebring, so neither is too bad of a drive. To date I would say Watkins Glen and Road Atlanta are my two favorite tracks.
 
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krisk

krisk

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My father my two brothers and I were also there at VIR as well as Watkins Glen. We didn’t go to summit point, I haven’t looked into getting any of the photos yet I will have to do that. I remember seeing your car there. The 4 cars we had brought were a 2024 992 GT3RS, 2024 Ford Mustang Dark Horse (Blue Ember), and two 2024 Mustang Gt’s (Black and Rapid Red). It was also our first time to VIR but we have been to Watkins Glen before. These are the only two photos that I took myself at the track

IMG_8605.webp


IMG_8606.webp
Yes, I remember you guys well. I saw your Canadian license plates quite a few times as you passed me. :cwl:
 

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What a great story, especially changing the transmission heat exchanger over 7 hours in 99 degree heat in a church parking lot (which required that pain in the butt transmission fill procedure).
I wholeheartedly agree! I admire you guys who have the talent and skill to fix things like this yourself.
 

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The Dark Horse and GT Performance Package have a separate transmission cooler mounted behind the radiator. For these cars the fluid cycles through the heat exchanger, then up to the cooler via a thermal bypass valve which opens once the transmission fluid reaches a certain temperature. So the transmission cooler only receives the fluid once the transmission heats up, but it constantly cycles through the heat exchanger.
Oh! That makes more sense. So I have a cooler behind the radiator. I need to look for that. Thank you.
 
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krisk

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I wholeheartedly agree! I admire you guys who have the talent and skill to fix things like this yourself.
It would be a challenge to track a vehicle without doing some self repair. At every track day there are quite a few vehicles stuck in the paddock broken down. Fortunately I’ve worked on my own vehicles since I started driving, so I have a decent ability to do repairs as needed. Also, having the Ford Service Manual makes a huge difference. I had my iPad setup next to me showing the replacement procure when I was swapping out the heat exchanger.
 

MidwayJ

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It would be a challenge to track a vehicle without doing some self repair. At every track day there are quite a few vehicles stuck in the paddock broken down. Fortunately I’ve worked on my own vehicles since I started driving, so I have a decent ability to do repairs as needed. Also, having the Ford Service Manual makes a huge difference. I had my iPad setup next to me showing the replacement procure when I was swapping out the heat exchanger.
I get it. I do track days rarely, and they were local.
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