Reading various GTR and Porsche forums, a number of people switched to FFL-4 fluid.

 

FFL-4 is the same viscosity as FFL-3 at 100 degC & 49 degC, but about 50 % thicker at 20 degC. Not certain this provides any different protection at full operating temps. The FFL-3 is more likely to ensure proper lubrication at lower temps. Remember, lubrication is internally sprayed onto one of the lay shafts in this tranny.

 

Blackstone replied:

So Jaguar T2R17199 does not appear to be FFL3 fluid. Next time I have some time, I will stop by dealership to get "virgin sample".

 

From David at Spec Clutch:
I am guessing that I will get the clutch within the next week or two at the latest. I am uncertain when the lightened flywheel will be arriving. However, since I plan on waiting until my current clutch disintegrates (and it will within 15k miles), I will not be installing it for a while anyway. If anyone has an immediate need for a clutch and would like to try this one, let me know. I would let you have the one I have on hand and would turn around right away and order another one (no waiting). This high performance clutch has been designed to handle 500 lb-ft of torque, well beyond the maximum 430 lb-ft produced by a double-pullied & tuned V6. It has also been designed to be compatible with both the Spec lightened flywheel as well as the OEM flywheel.

 

I would like to offer word of caution, a better clutch (that doesn't slip) would require lighter flywheel or you will tear apart your drivetrain downshifting. This is what happened to me with second generation clutch - the clutch was fine, but everything else went.

 

I am not certain that's a foregone conclusion as long as you're shifting smoothly.

 

I found, purchased and had Blackstone analyze Pentosin FFL3 fluid. Once they send me more empty containers, I will send Jaguar fluid for comparative analysis. Either way, here are the numbers:

 

 

At this point I am all but certain JLR fluid isn't FFL3. Fluid that came out of my gearbox had 2200 zinc, 3000 calcium, 2000 phosphorus. 100C viscosity is 9.36 to 6.97 of this fluid. However, I am not certain at what temperature would gearbox operate during heavy loads. Any idea?

 

 

I don't have any hard data, just some searching around, but I'd expect at least 100C. A diesel truck forum indicated that people were seeing 200F without towing, and 225F towing in hot weather.

 

 

Nope. Yep, yep. Definitely.

The discussion I found was specifically about manual transmissions.

 

 

It wasn't really an issue, but a discussion. The question was posed about the operating temperature of the gearbox oil under heavy use, so I searched for "manual transmission temperature." The ones who seem to care the most are the ones towing, so that's where I got the information.

On further thought, I recall a neighbor talking about an extra large oil cooler for his NSX. That was prepped for high-speed racing, specifically timed stages, where accuracy wins. Sustained 155mph needed a bit more cooling. Don't know if I have contact information though, as they recently moved.

 

I know I am opening up Unghind's box from Pandora, but he makes for good reading. Lance do you think a cooler could exist for the manual. I know after 4 hour fast drive, things do feel a bit different. Of course there is heat sink in the s/c which is a factor, but a tranny cooler does sound interesting!

 

 

 

I know it's a different car and all, but the sportier C7s with manuals all get tranny coolers. They are kind of in-unit with the differentials, but the diffs also get their own coolers.

 

The mystery deepens. I picked up a jug of T2R17199 fluid. Here it is next to Pentosin FFL-3.