Is anyone using Royal Purple?

[Chris_32212]

i am curious if anyone uses royal purple in the motor. swapping to synthetic trans and diff fluid can net some hp and i am just curious if anyone has done it. the GM part number for our trans fluid cross references to Royal Purple 5w30 XPR fluid (Extreme Performance Race). they also have a comperable synthetic gear oil. i talked to Bill B. and he said he didn't reccomend royal purple in the ZF trans simply because he doesn't have any experience with it. he gave me a part number for a german made trans fluid that is only available at BMW dealerships and he raves about how good it is but i am curious if it provides the HP gain that royal purple probably does. i know we are only talking a mabey a few hp for just the trans fluid but hey, every little bit helps right? let me know your thoughts on this.

Chris

[PhillipsLT5]

stay with bmw trans fluid
see
www.zfdoc.com

[Chris_32212]

i already know that thats the popular fluid... im not saying i am going to use royal purple. i just want to know if anybody has.

Chris

[tomtom72]

I can not comment on the oil as I've been a M1 10w-30 + Zddp, BMW TWS 10w-60 trans, GM stuff + 2x GM additive in the gear guy in my 90 for five yrs. Prior to that the orig owner just changed the motor oil & coolant. He only put 7400 miles on the car in 14.5 yrs so he never messed with anything else.

The one thing I can say is there have been the odd thread here and at CF about the use of other trans fluids and failures. I can't say that you can find any direct links to the failures and the oil used.....but it's just curious that all the failures seem to just have one common factor....which fluid was used. Now, I say "seem" because I've never read any of those threads about ZF failure where any other contributing factor was mentioned. You know like I've never seen any one post up that they neglected their clutch hyd. system, or that they drag race and don't use the clutch to shift, or that they road race and use the zf like a crash box, or that the C-beam was out of alignment, or any other factor that would account for a zf failure. The only two, well three if you count customer abuse, reasons for zf failure that I've seen posted about are: I didn't use the GM or the Castrol/BMW stuff, and reverse/sixth gear welded itself to the output shaft(?). I'm not clear about what exactly is with sixth/reverse....something about an internal lack of oiling as a design flaw from the factory????

I'm just saying in my 5 yrs of being a member of the registry this is what I've seen posted up about zf's and failures. The only other thing that I know for sure is that in the second owner's manual (the one in the pizza box) it says that if you are going to "drive your ZR-1 enthuiastically, you should switch all your fluids to synthetics.". That is in my 90's other owner's manual....at the time I know that the OEM fluids were all non-synthetic fluids.

Okay, I'll admit another thing.....I can't afford to have a trans failure, or any other major failures, so I use what seems to be the popular lube that seems to have no premature failures associated with it. My brain tells me that even with all synthetic fluids in my 90, I would only realize any performance gain if I put the car on a chassis dyno. Driving it on the street I'm sure my 'butt dyno' wouldn't know the difference, JMHO on the performance gains part. I use the synthetics because I think they protect my drivetrain better than dino based lubes, again JMHO.


Tom

[WB9MCW]

Originally Posted by PhillipsLT5

stay with bmw trans fluid
see
www.zfdoc.com

FROM THE ZF DOCTOR SITE >>>

(Q.) I just bought, at the local BMW dealership, 3 liters of the Castrol TWS 10W60 oil. I was surprised to see that it is motor oil. Not being a lubrication engineer myself, who did the investigation and determination that this product is compatible with and good for our ZF transmissions? Jim – Grand Sport Registry

(A.) Jim, the C4 Corvette ZF S6-40 6-speed transmission uses engine oil for lubrication. I was told by Jeff Henning, Warranty Administrator of ZF Industries North America, that Engineering of ZF Industries in Germany determined that the BMW imported Castrol (RS superseded by TWS) 10W-60 oil was the recommended alternative to the (GM P/N 1052931) factory-fill oil for use in the ZF S6-40 transmission. In effort to verify ZF Industries alternative lubricant recommendation, we ran our own test series on the BMW imported Castrol TWS 10W-60 oil. Independent testing of the transmission oil samples was sub-contracted out to CTC Analytical Services. The test series went as follows:
<1> Spectrographic analysis indicated that it is has full synthetic composition.
<2> After 2 hours of operation, approximately 100 miles, oil sample analysis tests indicated that the viscosity rating was reduced from 60 down to a 43 level. No need to worry, this is a normal occurrence for this heavier type of oil. I attribute this to microscopic-level lubricant-strand trimming through operational loading where all of the oil contents has been passed through gear pressure-loading regions at least a few times.
<3> At 200 miles, the viscosity level stabilized at a 42 level viscosity since the 100 mile oil analysis test results.
<4> At 5000 miles, the oil analysis test results indicated a 40 level viscosity.
The test-transmission was completely disassembled and checked for wear. There were no signs of carbon film like experienced with the factory-fill oil. The phosphor-bronze lined synchronizers had no glazing and experienced an average mass loss of approximately 4% based on reserve-wear-range mass equivalency between 0.062"(new) and 0.048"(spent)
gap wear/mass measurements.
<5> At 10,000 miles, the oil analysis test results indicated a 39 level viscosity.
<6> At 12,500 miles, the oil analysis test results indicated a 37 level viscosity.
<7> At 15,000 miles, the oil analysis test results indicated a 34 level viscosity.
The test-transmission was again completely disassembled and checked for wear. There were no signs of carbon film like experienced with the factory-fill 30 oil. The phosphor-bronze lined synchronizers had no glazing and experienced an average mass loss of approximately 17% based on reserve-wear-range mass equivalency between 0.062"(new) and 0.048"(spent) gap wear/mass measurements.
<8> At 15,000 miles the oil had enough phosphor-bronze particles suspended
in it that deposits began building up inside of the synchronizer sliding
sleeves from the normal centrifuge-like rotational occurrence.
In Conclusion, until someone invents a copper magnet, we recommend that the ZF S6-40 6-speed transmission oil be changed at 10,000 - 12,000 mile intervals so as to minimize the amount of deposits of the suspended spent synchronizer material from collecting in critical component contact surface areas.

[Aurora40]

Originally Posted by Chris_32212

i am curious if anyone uses royal purple in the motor. swapping to synthetic trans and diff fluid can net some hp and i am just curious if anyone has done it.

I would bet most of us use synthetic motor oil, trans fluid, and diff fluid. It just doesn't generally happen to be Royal Purple for said fluids.

And I agree with Tom. Personally I'll go with the safe play vs the one that isn't. Even though something else may work just fine or better. So for now it's Redline oil (full of ZDDP yumminess), Castrol trans fluid, and Mobil 1 diff fluid. I keep thinking I should go to M1 high mileage engine oil, as it has the "normal" amount of ZDDP and is cheaper, but something about that "high mileage" in a 40,000 mile car that I can't explain bugs me...

[jonszr1]

i have 4000 reasons to use the bmw 0-06 that bill recommends. i had the 6th gear reverse weld problem in my blk car. if i lose a few hp to not have 4000 dead presidents leave my pocket again its good by me

[jonszr1]

opps it castrol 0-60

[PhillipsLT5]

see
www.zr1specialist.com
for motor oil
Amsoil 10/40

[Chris_32212]

is the castrol and BMW trans fluid synthetic? i would venture to guess that it is but does anyone know for sure?

Chris