S197 Diff fluid

[Tim.ocon]

Had an interesting weekend at the track and had to replace an axel seal

I put 75W90 in when I replaced it which definitely is wrong. But I didn’t double check what I was told so that is on me

Ford recommends a 75W140 I was wondering what other folks run in their track cars

I currently have 273 gears but will be upgrading to 355 gears in the future once I figure out a driveshaft.
Is there a different fluid I should use to prevent overheating

 

[JDee]

With my '16 I got axle overheat warnings on warm days at Mosport with the stock fill. I switched to Redline 75W140 and that was better, but it still would overheat now and then. The only real solution is a diff cooler, which is not that hard to do. Tilton lube pump mounted in the trunk, cooling matrix with built in fan under the trunk and some wiring to run it.
The diff died anyway, probably from all the abuse it had already taken.

 

[Tim.ocon]

With my '16 I got axle overheat warnings on warm days at Mosport with the stock fill. I switched to Redline 75W140 and that was better, but it still would overheat now and then. The only real solution is a diff cooler, which is not that hard to do. Tilton lube pump mounted in the trunk, cooling matrix with built in fan under the trunk and some wiring to run it.
The diff died anyway, probably from all the abuse it had already taken.

I had never had mine over heat until I refilled the diff after doing the axel seal. I’m sure I’ll have to get a diff cooler eventually

I’ll look into the redline fluid

 

[stevbd]

I would run the spec fluid. Diff coolers are common with the S550 but not so much the S197. The solid rear axle with its axle tubes dissipates heat better than the IRS in the S550.

Rear axle seals often fail due to heat from the rear brakes, not overheated diff fluid, especially if you are using stability control on track (which is often desirable). The common fix is to either turn stability control completely off or use the 14" GT500 rear brake rotors and caliper mounting bracket, which moves heat away from the axle seal.

 

[EF1]

Had an interesting weekend at the track and had to replace an axel seal

I put 75W90 in when I replaced it which definitely is wrong. But I didn’t double check what I was told so that is on me

Ford recommends a 75W140 I was wondering what other folks run in their track cars

I currently have 273 gears but will be upgrading to 355 gears in the future once I figure out a driveshaft.
Is there a different fluid I should use to prevent overheating
View attachment 97986

I run Redline 75w140 and have not had a heat or axle seal problem yet in my 2011. That is with Ford Performance finned aluminum cover (holds extra quart), Eaton TruTrac differential, 4:10 gears, 13.8” rear rotors and dust shields removed. Oh and I have run it at Barber in July with air temps in the high 90’s.

 

[Tim.ocon]

I would run the spec fluid. Diff coolers are common with the S550 but not so much the S197. The solid rear axle with its axle tubes dissipates heat better than the IRS in the S550.

Rear axle seals often fail due to heat from the rear brakes, not overheated diff fluid, especially if you are using stability control on track (which is often desirable). The common fix is to either turn stability control completely off or use the 14" GT500 rear brake rotors and caliper mounting bracket, which moves heat away from the axle seal.

I had blown a piston seal a little while back and I suspect the reason the axel seal failed is due to the brake fluid deteriorating the axel seal. I replaced the diff with the incorrect fluid after changing the axel seal.
Is there a specific spec fluid you would recommend?

What is involved in the 14” gt500 rotor swap?

 

[stevbd]

I have the same exact setup as @EF1 except I have a 3.31 axle ratio.

This is the 14" (13.8" actually) kit using Ford parts, it is what I used: https://www.cjponyparts.com/ford-gt...MI5o7xyoiJiAMVRWlHAR0Sfx97EAQYASABEgLLufD_BwE

This kit gets you to the same place with an easier caliper mounting bracket (you don't have to remove the axles again to install the mounting bracket), but arguably it may be a little less secure. I don't know if it is a meaningful difference: https://lmr.com/item/SVE-GT500AB-K/...MI5o7xyoiJiAMVRWlHAR0Sfx97EAQYAyABEgLVZvD_BwE

 

[EF1]

I have the same exact setup as @EF1 except I have a 3.31 axle ratio.

This is the 14" (13.8" actually) kit using Ford parts, it is what I used: https://www.cjponyparts.com/ford-gt...MI5o7xyoiJiAMVRWlHAR0Sfx97EAQYASABEgLLufD_BwE

This kit gets you to the same place with an easier caliper mounting bracket (you don't have to remove the axles again to install the mounting bracket), but arguably it may be a little less secure. I don't know if it is a meaningful difference: https://lmr.com/item/SVE-GT500AB-K/...MI5o7xyoiJiAMVRWlHAR0Sfx97EAQYAyABEgLVZvD_BwE

I used the Ford parts purchased from a local dealer for much less than the kit from CJ but it was several years ago. The rotors were still available from dealer a few months ago. I purchased a pair for less than $200. Not sure if the GT500 caliper mounting brackets are still in dealer stock.

 

[mwjscn]

DR3Z-2C101-A & DR3Z-2C100-A are still available if you decide to go that route. $170 + $15-20 shipping from places like Tasca. My local dealer is about $50 more expensive on the base price with their free shipping, but you can check locally as they're always different. I have the OEM ones in a box, but will probably use the Blowfish version since I could get my hands on a pair.

 

[67GTA]

I had blown a piston seal a little while back and I suspect the reason the axel seal failed is due to the brake fluid deteriorating the axel seal. I replaced the diff with the incorrect fluid after changing the axel seal.
Is there a specific spec fluid you would recommend?

What is involved in the 14” gt500 rotor swap?

The only thing I would add that hasn’t been mentioned yet - make sure your axle vent is functioning properly. I’ve had more seals fail from pressure building within the housing. The OEM vents are notorious for melting or getting damaged by the OTA exhaust pipes, especially if the car has been lowered at all.

 

[Tim.ocon]

The only thing I would add that hasn’t been mentioned yet - make sure your axle vent is functioning properly. I’ve had more seals fail from pressure building within the housing. The OEM vents are notorious for melting or getting damaged by the OTA exhaust pipes, especially if the car has been lowered at all.

Oh don’t worry. When the diff got hot and the fluid came out of the vent and covered the rear of the car. It’s all functioning properly

 

[67GTA]

Oh don’t worry. When the diff got hot and the fluid came out of the vent and covered the rear of the car. It’s all functioning properly

I can smell it just from your description

 

[KazarS197]

Like @67GTA said some kind of expansion will help. I am running a JLT expansion tank. Unfortunately they are discontinued. Everything else out the is pricey. I just found this looking around - DR3Z-4022-A "KIT HOSE ASY" . Might be a cheap fix to get you though. I think it was the original TSB for the leaking vents. It's a hose extension that has the vent sitting higher than having it connected straight to the axle. It also gives you a tad of expansion. Just me - I wonder if you could keep going with more hose , like another foot up along the frame attached with zip ties for more volume. The only other thing I would do is use some high temp gasket maker to the fitting and some around the fitting once it's tightened. My JLT fitting ended up leaking. Permatex motoseal fixed the issue. I used that stuff on modified chainsaws with 180-200 psi compression as the alone cylinder gasket.

 

[mwjscn]

I think it was the original TSB for the leaking vents.

The original TSB was AR3Z-4A058-B aka 'the turkey baster', but then people started having those exploding due to the proximity to the over-axle exhaust pipe

 

[Mike_FL]

I have the SVE adapter plates to fit the GT500 rotors. They work fine, I do get a groaning sound when reversing though, no idea why but apparently it’s common.
Do the GT calipers fit ok when using the ford oem GT500 brackets? I’m sure I read somewhere that you have to grind a bit of the rear caliper to fit

 

[Stangra]

.

 

[EF1]

I have the SVE adapter plates to fit the GT500 rotors. They work fine, I do get a groaning sound when reversing though, no idea why but apparently it’s common.
Do the GT calipers fit ok when using the ford oem GT500 brackets? I’m sure I read somewhere that you have to grind a bit of the rear caliper to fit

It depends on year. Early S197 calipers usually need a little clearancing with a file. Later ones fit just fine.

 

[Stangra]

Like @67GTA said some kind of expansion will help. I am running a JLT expansion tank. Unfortunately they are discontinued. Everything else out the is pricey. I just found this looking around - DR3Z-4022-A "KIT HOSE ASY" . Might be a cheap fix to get you though. I think it was the original TSB for the leaking vents. It's a hose extension that has the vent sitting higher than having it connected straight to the axle. It also gives you a tad of expansion. Just me - I wonder if you could keep going with more hose , like another foot up along the frame attached with zip ties for more volume. The only other thing I would do is use some high temp gasket maker to the fitting and some around the fitting once it's tightened. My JLT fitting ended up leaking. Permatex motoseal fixed the issue. I used that stuff on modified chainsaws with 180-200 psi compression as the alone cylinder gasket. View attachment 97992

I was using the Cortex differential breather/catch tank mounted at the recommended location on the Cortex differential cover. It wasn't much higher than the stock axle vent and I still had a mess underneath the car.
I moved it up and mounted it next to the gas fill pipe, problem solved.

CorteX Differential Breather Vent Catch Tank Kit - Mustang 8.8 Rearend

RAB-40-1000

www.cortexracing.com

 

[Mike_FL]

It depends on year. Early S197 calipers usually need a little clearancing with a file. Later ones fit just fine.

Is 2012 early or later?

 

[EF1]

Is 2012 early or later?

Later