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9
11
Exp. Type
HPDE
Exp. Level
5-10 Years
Louisiana
I just picked up a 2018 GT350. Car is stock, from what I can tell. This is my daily driver and plan to do 4-6 HPDE track days/yr and 4-6 autocrosses/yr. I live in south Louisiana (hot and humid). Prior experience is HPDE for past 8 years (previously in a 2010 Corvette and a 2004 Honda S2000). I'm not looking to set any lap records or win any races, just weekend warrior fun. This is my first Ford and looking for any advice.

My plan so far:
Steeda Clutch spring
Passenger catch can
Brake fluid: RBF 600
Tranny fluid: Amsoil ATF signature series (blue cap)
Diff oil: Amsoil Severe gear 75W-90
Before each event, all I do is change engine oil, change street brake pads to track pads, flush brake fluid, and flush clutch fluid (suck out the old fluid in reservoir, replace with clean RBF, pump clutch 15 times, repeat until reservoir fluid is clean ).
I change tranny fluid and diff oil yearly.

Questions:
Brake pads, need help. These rotors are expensive @ $300/each (the S2000 rotors were $75/each), so I'm looking for a street pad and a track pad that are "rotor friendly". I actually find the stock pads more grabby than I need for the street. Which is fine, but I don't drive aggressively, so all I "need" is a decent street pad that is rotor friendly and won't completely suck at autocross. For track pads, this is the heaviest car I've had, and at NOLA, the turn 1 braking zone goes from 145mph to 55mph. Not sure what pad to run, maybe G-Lock?
Is flushing the brake fluid and clutch before very track event over kill?
Will my procedure for flushing the clutch fluid work in a GT350?
Is changing the tranny fluid and diff oil once a year enough?
Everyone says 75W-140 diff oil for track work. Do you think 75W-90 is the right call, given this is a 80-90% street driven car, or should I use 75W-140?
Are there any bolts, nuts, clips, etc that need to be replaced after one use (I've seen some stuff about replacing the OEM caliper bolts), or anything weird that I should be aware of ?
Anything wrong with my plan above?
Anything else?
 

JDee

Ancient Racer
1,778
1,978
Exp. Type
W2W Racing
Exp. Level
20+ Years
5 miles from Mosport
I just picked up a 2018 GT350. Car is stock, from what I can tell. This is my daily driver and plan to do 4-6 HPDE track days/yr and 4-6 autocrosses/yr. I live in south Louisiana (hot and humid). Prior experience is HPDE for past 8 years (previously in a 2010 Corvette and a 2004 Honda S2000). I'm not looking to set any lap records or win any races, just weekend warrior fun. This is my first Ford and looking for any advice.

My plan so far:
Steeda Clutch spring
Passenger catch can
Brake fluid: RBF 600
Tranny fluid: Amsoil ATF signature series (blue cap)
Diff oil: Amsoil Severe gear 75W-90
Before each event, all I do is change engine oil, change street brake pads to track pads, flush brake fluid, and flush clutch fluid (suck out the old fluid in reservoir, replace with clean RBF, pump clutch 15 times, repeat until reservoir fluid is clean ).
I change tranny fluid and diff oil yearly.

Questions:
Brake pads, need help. These rotors are expensive @ $300/each (the S2000 rotors were $75/each), so I'm looking for a street pad and a track pad that are "rotor friendly". I actually find the stock pads more grabby than I need for the street. Which is fine, but I don't drive aggressively, so all I "need" is a decent street pad that is rotor friendly and won't completely suck at autocross. For track pads, this is the heaviest car I've had, and at NOLA, the turn 1 braking zone goes from 145mph to 55mph. Not sure what pad to run, maybe G-Lock?
Is flushing the brake fluid and clutch before very track event over kill?
Will my procedure for flushing the clutch fluid work in a GT350?
Is changing the tranny fluid and diff oil once a year enough?
Everyone says 75W-140 diff oil for track work. Do you think 75W-90 is the right call, given this is a 80-90% street driven car, or should I use 75W-140?
Are there any bolts, nuts, clips, etc that need to be replaced after one use (I've seen some stuff about replacing the OEM caliper bolts), or anything weird that I should be aware of ?
Anything wrong with my plan above?
Anything else?
Do you know if your car has a diff cooler on it? If it doesn't you should plan to put one on. MMR makes a good kit for Mustangs. Pretty straighforward to install and it will save your diff.
They're telling you 75W-140 because that's what you need on track. 75W90 will overheat quickly if you have any long straights and run on hot days. The heat will kill your diff over time. 75W140 will also overheat, I ran that in my '16 and used to get axle overheats all the time on hot days and it did kill the diff, hence the advice to put a diff cooler on it. I had the heat sensor in my diff, so I got axle heat warnings on the centre screen. Not all cars have that sensor so a lot of diffs are dying quietly until one day there's this noise back there......and you're now in for a new diff.
Even a high end oil won't save the day, I ran synthetic RedLine 75W140 and still lost the diff.
There's no downside to using 75W140 on the street, though you might get 1/100th of a MPG less fuel economy.
Bleed the brakes if you think you've got them too hot and note what the fluid looks like. Be proactive and put brake cooling on if you're concerned about it. Vorshlag has flaps that help a lot, I would recommend you look into them and a way to feed air to the flaps from the grille/bumper area. The PP1 nose was set up to make that job easier.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,356
8,207
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
You have numerous Sponsor Experts on this site for brake pad recommendations , so feel free to contact any or all of them as most of us have used their advice and products!
Capaldi Racing. OPMustang , KNS Brakes, EBC Brakes

Great looking GT 350 and welcome to TMO.
 
584
987
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin
I just picked up a 2018 GT350. Car is stock, from what I can tell. This is my daily driver and plan to do 4-6 HPDE track days/yr and 4-6 autocrosses/yr. I live in south Louisiana (hot and humid). Prior experience is HPDE for past 8 years (previously in a 2010 Corvette and a 2004 Honda S2000). I'm not looking to set any lap records or win any races, just weekend warrior fun. This is my first Ford and looking for any advice.

My plan so far:
Steeda Clutch spring
Passenger catch can
Brake fluid: RBF 600
Tranny fluid: Amsoil ATF signature series (blue cap)
Diff oil: Amsoil Severe gear 75W-90
Before each event, all I do is change engine oil, change street brake pads to track pads, flush brake fluid, and flush clutch fluid (suck out the old fluid in reservoir, replace with clean RBF, pump clutch 15 times, repeat until reservoir fluid is clean ).
I change tranny fluid and diff oil yearly.

Questions:
Brake pads, need help. These rotors are expensive @ $300/each (the S2000 rotors were $75/each), so I'm looking for a street pad and a track pad that are "rotor friendly". I actually find the stock pads more grabby than I need for the street. Which is fine, but I don't drive aggressively, so all I "need" is a decent street pad that is rotor friendly and won't completely suck at autocross. For track pads, this is the heaviest car I've had, and at NOLA, the turn 1 braking zone goes from 145mph to 55mph. Not sure what pad to run, maybe G-Lock?
Is flushing the brake fluid and clutch before very track event over kill?
Will my procedure for flushing the clutch fluid work in a GT350?
Is changing the tranny fluid and diff oil once a year enough?
Everyone says 75W-140 diff oil for track work. Do you think 75W-90 is the right call, given this is a 80-90% street driven car, or should I use 75W-140?
Are there any bolts, nuts, clips, etc that need to be replaced after one use (I've seen some stuff about replacing the OEM caliper bolts), or anything weird that I should be aware of ?
Anything wrong with my plan above?
Anything else?

GLOC seems to be the preferred pad for mustangs. OMP mustang will get you all hooked up with those. I think you even get a discount for being a member.
I bought an Amazon tester for brake fluid, it works really well. I track my car A LOT and we change it about every 3 events.
Trans and Diff.. maybe every 6 months but again we are running the car HARD.
Because you have a 350, keep an eye on that oil. That will be your biggest worry. I had a 2017. Awesome car.
 
9
11
Exp. Type
HPDE
Exp. Level
5-10 Years
Louisiana
Do you know if your car has a diff cooler on it? If it doesn't you should plan to put one on. MMR makes a good kit for Mustangs. Pretty straighforward to install and it will save your diff.
They're telling you 75W-140 because that's what you need on track. 75W90 will overheat quickly if you have any long straights and run on hot days. The heat will kill your diff over time. 75W140 will also overheat, I ran that in my '16 and used to get axle overheats all the time on hot days and it did kill the diff, hence the advice to put a diff cooler on it. I had the heat sensor in my diff, so I got axle heat warnings on the centre screen. Not all cars have that sensor so a lot of diffs are dying quietly until one day there's this noise back there......and you're now in for a new diff.
Even a high end oil won't save the day, I ran synthetic RedLine 75W140 and still lost the diff.
There's no downside to using 75W140 on the street, though you might get 1/100th of a MPG less fuel economy.
Bleed the brakes if you think you've got them too hot and note what the fluid looks like. Be proactive and put brake cooling on if you're concerned about it. Vorshlag has flaps that help a lot, I would recommend you look into them and a way to feed air to the flaps from the grille/bumper area. The PP1 nose was set up to make that job easier.
Thanks! NOLA has a long front straight and plenty of hot days, I'll swap in 75W-140 before the next event. Luckily, I do have a factory diff and tranny coolers and gauges on the center screen. I read that you want to to keep Diff < 250°F, Tranny < 225°F, and Cylinder head < 240°F. Does that sound right?
 
9
11
Exp. Type
HPDE
Exp. Level
5-10 Years
Louisiana
GLOC seems to be the preferred pad for mustangs. OMP mustang will get you all hooked up with those. I think you even get a discount for being a member.
I bought an Amazon tester for brake fluid, it works really well. I track my car A LOT and we change it about every 3 events.
Trans and Diff.. maybe every 6 months but again we are running the car HARD.
Because you have a 350, keep an eye on that oil. That will be your biggest worry. I had a 2017. Awesome car.
Yeah, I was warned about oil consumption. A brake fluid tester is a foreign concept for me. I need to check in to that, especially if it'll save me from doing unnecessary work. Thanks for all the input.
 

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