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School me on fluids - getting ready to freshen up the Boss.

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I've read several different threads about fluid changes and all the different brands/types people are using. I'd like to keep all the info in one thread if possible, so I apologize if this is repeat information. Please let me know if I have these right and/or if you suggest on something else.

Motor oil - 5w50 full synthetic
-Motorcraft
-Mobil 1 full synthetic
-Amsoil full synthetic

Transmission oil
-Refdline MTL? Weight?

Brake fluid
-high-temp Dot 4 (i.e.: ATE Super Blue, Motul, etc?)

Rearend gear oil
-Amsoil? Weight?
-motorcraft? Weight?


Sorry for all the rookie questions. It just seems the Boss is so much more 'delicate' and requires special attention to detail ;D I've been so used to the older mustangs - I used to just jack them up at the k-member or rearend, swap fluids/filters, and beat on them :p Don't want to make any mistakes with the BOSS or I might get fired! :-\
 
I'll give you my opinion and what I use, but you have to make your decision at the end :p

Engine, I use Mobil1 5w50. I think the key here is to stick with 5w50, because the valvetrain and timing system were designed with certain viscosities in mind. FYI Mobil1 is on sale at NAPA, at the moment.

Transmission, I use BG synchroshift II. Forgot what viscosity it was, but they only have one. It has given no trouble at the track or during winter. I had my transmission internals upgraded when my clutch blew. The mechanic said everything looked brand new in there, so I stuck with BG.

Brake, I use Castrol SRF. If you don't track regularly, then it's overkill and expensive. I'd skip ATE blue, since it's not DOT legal anymore and go with another DOT4.

Differential, I use Amsoil severe gear oil 75w140. Again, I've had the diff inspected by shops, and they all said the gears look new, even after 30k miles. The amsoil seems to handle the heat well. I replace it 1-2 times per year, depending on the amount of events I do.

Hope this helps ;D
 
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FD is right, stick with 5W-50. The algorithms for the timing system were all designed with this oil weight in mind.

I'm really liking Driven racing oil for the Diff and the engine. They use a better base oil than anyone and make oil specifically for the Ford Coyote engine (FR50). It's not cheap. You can get both from Summit (both 5W-50 and 75W-140 for the diff). You don't need friction modifier since you have a Torsen (if you have Recaro seats, then you have a Torsen Diff). I personally do not buy anything from Amsoil simply because I hate their marketing. I also don't like they way they trash every other company out there as if there is a vast conspiracy to hide the fact that only Amsoil is the only thing that should be used. For those that use Amsoil, this is not a dig at you guys. It's just my opinion. But, I digress.....

Brembo LCF600 is really good brake fluid and I just learned that it is really good for keeping piston seals alive for a long time. It's easy to get and totally compatible with any Ford that is Brembo equipped from the factory. High performance Brake Fluid should be flushed at least annually depending on how often and how hard you track it. I think it's best practice to completely flush brake out of the brake system and clutch line once a year.

For the tranny, I just stick with the Motorcraft XT-M5-QS.
 
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Bay Area
This is just my opinion but if you are not going to track your car right now and just get used to it I would leave it as stock fluids, besides the brake fluid but it is fine if your not driving like you stole it all the time. You only have what 3000ish miles on it? And you know it was babied, right? I would change the oil and drive it. Change your shifter when you change the trans fluid so you get the full benefit of the change. Once you start tracking, autocross, drag racing then spend the time and money. Oh and you can still jack it up and change your fluids. PM me I'll come help you out.
 
Thanks for the recommendations, all!

@byronj I was teasing when I noted that you can'tjust jack up the Boss :D. I know it's just another car but I definitely want to use the correct fluids. I don't plan to track it heavily, but it is in my pipeline before the end of the year. I certainly want the car to be ready for the abuse nonetheless. I don't intend to replace the shifter yet, but I do want to replace the transmission fluid with something along the lines of Redline MTL as I've heard that it eliminates some of the notchy shifting (although I have yet to experience this myself).

The current motor oil/filter actually only has 1600 miles since the last change, but I'd prefer to start fresh for piece of mind. So much to do, so little time :-\
 
F.D. Sako said:
FYI Mobil1 is on sale at NAPA, at the moment.
Thanks. I'll go pick some up this weekend.

FWIW In the MT-82 I've run stock fluid from the factory, Redline and the Motorcraft XT-M5-QS that @Big Taco suggested and liked the Motorcraft the best. It had the best shifting when cold and was as good as the Redline when hot. It's also what Ford recommends which was a change from the original fluid in the MT-82.
 
VoodooBOSS said:
Thanks. I'll go pick some up this weekend. Will I also need a motorcraft oil filter or will any standard Fram or Wix filter work fine?

FWIW In the MT-82 I've run stock fluid from the factory, Redline and the Motorcraft XT-M5-QS that @Big Taco suggested and liked the Motorcraft the best. It had the best shifting when cold and was as good as the Redline when hot. It's also what Ford recommends which was a change from the original fluid in the MT-82.


I'll be at Napa this weekend too!

Thanks for the clarification Rick. I thought the recommended Motorcraft transmission fluid was the "original" type that was later upgraded. Again, so much to be learned still ;)

Btw, is Motorcraft fluid only sold at Ford dealerships? If not, any recommended retail stores?
 
I'm biased (because I sell it) but BG Syncro Shift II for the transmission and BG Ultra Guard Heavy Duty LS (75W-140) for the rear axle. Hundreds of happy Customers. Ford and GM Service departments use BG Products and Machines. It's more money but they have really good products. Some Ford dealers don't even stock the OE fluids, just BG.

Even street-driven-only cars benefit greatly from BG products. It helps with gear nibble and stands up well to being overheated during track use. Plus they offer an additive package which allows you to replenish the fluid to help extend fluid changes.

A note on Torsen Diff's: Run the additive. It does effect the bias of the differential even though it does not have clutches. Ford typically designs the dynamics around the use of the additive being used. Most aftermarket fluids have rear axle lube with the additve already added in. It's why we carry only the 'LS' version fluids.

Ford DOT4LV Brake Fluid is pretty good (same as Pentosin)I carry the full Motorcraft Line as well and Castrol SRF. The Motorcraft Brake Fluid just needs to be flushed a couple times a year if you track the car because like any DOT 4 if Loves Moisture. SRF is expensive but lasts at least twice as long and is safe in the Ford Brake system. Some of the other fluids have given people issues with pedal feel.

I'm not even going to touch on engine oils, those discussions tend to get way too emotionally charged. Stick with OE weight, Ford fluids are not that bad unless you base everything off the internet. Running 5W-20 in my '15 it should have blown up with all the track time, oil samples told me something very different. Any quality engine oil should be fine.
 
Sydewaysix said:
Thanks for the clarification Rick. I thought the recommended Motorcraft transmission fluid was the "original" type that was later upgraded. Again, so much to be learned still ;)

Btw, is Motorcraft fluid only sold at Ford dealerships? If not, any recommended retail stores?
Both are Motorcraft but different fluid. They changed it. FWIW the transmissions are weak in these cars so I recommend using the recommended fluids for warranty purposes. Take that from a guy that blew his motor on track and also had my trans rebuilt twice all covered under warranty. The guy that bought my car broke the trans again and Ford finally replaced it.
 
VoodooBOSS said:
Both are Motorcraft but different fluid. They changed it. FWIW the transmissions are weak in these cars so I recommend using the recommended fluids for warranty purposes. Take that from a guy that blew his motor on track and had it replaced under warranty for free and also had my trans rebuilt twice. The guy that bought my car broke the trans again and Ford finally replaced it.

Will do, thank you sir! What about oil filters? Motorcraft only or any brand is ok?
 

buland

One of the rare Boss LS in Switzerland
I use the FRPP High Performance OilFilter and Mobile1 5W/50 Oil




https://performanceparts.ford.com/part/CM-6731-FL820
 
This is what I use:
Engine: Amsoil 5-50 signature and EaO17 filter.
Trans: 2 qts. Of Amsoil synthetic synchromesh and .7 qt. Amsoil syn. gear lube.
Brakes: Brembo LCF 600 plus, (I have 15" 6p brakes).
Gear oil: Amsoil or Ford full synthetic 75-140
Clutch: Brembo LCF 600+, (separate res.)
 

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