Fluid type & capacity?
Race Director
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From: Kingman AZ
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
In Gordon Killebrew's class he recommends draining and filling the rear end with 2 bottles of GM posi additive and then fill with Mobil 1 differential fluid until reaches the level of the drain hole.
I'm at work now so cannot look up the tranny info. If I recall though he recommended synthetic for that also.
I'm at work now so cannot look up the tranny info. If I recall though he recommended synthetic for that also.
Melting Slicks
Joined: Feb 2006
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From: Columbia SC
From the GM 1996 corvette service manual on page 7-7 of book 2 for the ZF S6-40 6-Speed Manual Trans (RPO ML9) the recommended lub is GM Gear Lub P/N 1052931 and amount is 2.12 liters or 4.4 pints.
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Racer
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From: Goodyear Arizona
Originally Posted by Fast Cop
From the GM 1996 corvette service manual on page 7-7 of book 2 for the ZF S6-40 6-Speed Manual Trans (RPO ML9) the recommended lub is GM Gear Lub P/N 1052931 and amount is 2.12 liters or 4.4 pints.
Originally Posted by CentralCoaster
Buy (3) quarts of tranny fluid, (3) quarts of rear gear oil, and (2) four oz bottles of posi additive.
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From: Kingman AZ
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
I'm home now. Here is the text from Chris Petris' C4 class that I took last year: 6-speed transmission. Drain the transmission. A large 14mm Allen wrench is necessary. Remove the fill pulg. Refill with 10W30 oil.
Differential Service: The differential should be serviced every 25,000-30,000 miles. You can use a suction gun and remove the used differential gear oil, however this is very difficult to do and most debris is left on the bottom of the differential case. I have created a differential drain plug kit to remedy the problem. I refill the differential with Mobil One synthetic gear oil and General Motors differential positraction additive.
Note (from me): He does not list the weight of the differential lubricant here and I believe you can buy his differential drain plug kit from Ecklers. I have seen it posted either here or at www.corvetteactioncenter.com
OK, this from Mike Antonick's Cor-vette Specs book for the 1996 Corvette: Rear Axle Unit, Lubricant Capacity: 3.0 pt (auto trans), 2.75 pt (manual trans). Lubricant type recommended: GL-5 gear lubricant 80-W90.
Goodnight, headed for the pillow now.
Differential Service: The differential should be serviced every 25,000-30,000 miles. You can use a suction gun and remove the used differential gear oil, however this is very difficult to do and most debris is left on the bottom of the differential case. I have created a differential drain plug kit to remedy the problem. I refill the differential with Mobil One synthetic gear oil and General Motors differential positraction additive.
Note (from me): He does not list the weight of the differential lubricant here and I believe you can buy his differential drain plug kit from Ecklers. I have seen it posted either here or at www.corvetteactioncenter.com
OK, this from Mike Antonick's Cor-vette Specs book for the 1996 Corvette: Rear Axle Unit, Lubricant Capacity: 3.0 pt (auto trans), 2.75 pt (manual trans). Lubricant type recommended: GL-5 gear lubricant 80-W90.
Goodnight, headed for the pillow now.
Race Director
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From: Glendale, AZ
Originally Posted by Fast Cop
From the GM 1996 corvette service manual on page 7-7 of book 2 for the ZF S6-40 6-Speed Manual Trans (RPO ML9) the recommended lub is GM Gear Lub P/N 1052931 and amount is 2.12 liters or 4.4 pints.
i bought the ROYALPURPLE 75w90 it already has the friction modifier in it!
http://royalpurple.com/techa/whichoil.html
go back to the AZ forum and PM sidewinder - he's our resident independent certified oil expert - they don't call him SKID for nothing!
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by Runemaster
Well, gear lube is not tranny fluid. And I'd rather not buy GM part# whatever, I'd prefer to use synthetic stuff. I also don't think that part # is Dexron III.
If the ZF6 calls for ketchup, then ketchup is your transmission fluid.
Last edited by CentralCoaster; Jul 7, 2006 at 03:34 AM.
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Thread Starter
Racer
Joined: Apr 2006
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From: Goodyear Arizona
Originally Posted by CentralCoaster
I never mentioned ATF. If the ZF6 calls for ketchup, then ketchup is your transmission fluid.
If the ZF6 calls for ketchup, then ketchup is your transmission fluid.
Originally Posted by CentralCoaster
Buy (3) quarts of tranny fluid, (3) quarts of rear gear oil, and (2) four oz bottles of posi additive.
Does anyone know what GM Gear Lub P/N 1052931 is, weight and type wise?
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
My bad, I thought you were asking us for help. But since you're nit picking it, you might want to contact these guys and let them know they need to rename their stuff:
Some manual transmissions take gear oil, some take ATF, some take motor oil. And for fun, I'm using Mobil 1 ATF for power steering fluid.
Some manual transmissions take gear oil, some take ATF, some take motor oil. And for fun, I'm using Mobil 1 ATF for power steering fluid.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by 4Ever21
hey CC, the early C4's also used 80w90 in the rear axle didnt they?
I believe so. The optional 75w140 is too thick and will probably break down to a 75w90 anyways. And it will sap your fuel mileage and hp. Dale Earnhardt once ran qualifying laps with teflon coated gears and no lube, he won the pole. They had forgotten to fill the diff by accident.
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Racer
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From: Goodyear Arizona
Originally Posted by CentralCoaster
My bad, I thought you were asking us for help. But since you're nit picking it, Some manual transmissions take gear oil, some take ATF, some take motor oil. And for fun, I'm using Mobil 1 ATF for power steering fluid.
I asked for SPECS, and you responded "go buy some tranny fluid" which is far from specific. So, while you may think you were being helpful (or cute or cool or trendily angst ridden), you were actually merely wasting time and forum space with a gerneralized response that failed to put the "specific" in "specs". And yet, somehow, you think you were offering help.
Sorry if you find my desire for precise information "nit picking", but I'm weird like that... Have a nice life. 
Team Owner
Joined: May 2002
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Ok then, go get an eyedropper and measure out 34.6343 oz and squeeze it into your transmission.
That's not how its done, you round up to the next quart, purchase that many, and you pump it in until it comes out the fill hole. Any discussion beyond that is wasting time. And if you don't know what type of fluid goes in the ZF6, you must have born yesterday, it's a repetitive discussion topic on here, and to ask without searching is "wasting time and forum space."
I have never found a fill capacity published for the Corvette D44.
The GM fluid previously mentioned for the ZF6 is a 5w30. Some have said it was originally manufactured by Pennzoil. But then some have also said that gear oils and motor oils don't use the same viscocity scale, so take it for what its worth.
Synthetic vs non-synthetic should not be your first criteria for the ZF6. You'll probably find that although harder to come by, the GM fluid is preferred. Testing by ZFdoc and experience from myself and some forum members, raises doubts about the use of the Castrol synthetic TWS 10-60 motor oil.
You have the wrong attitude.
That's not how its done, you round up to the next quart, purchase that many, and you pump it in until it comes out the fill hole. Any discussion beyond that is wasting time. And if you don't know what type of fluid goes in the ZF6, you must have born yesterday, it's a repetitive discussion topic on here, and to ask without searching is "wasting time and forum space."
I have never found a fill capacity published for the Corvette D44.
The GM fluid previously mentioned for the ZF6 is a 5w30. Some have said it was originally manufactured by Pennzoil. But then some have also said that gear oils and motor oils don't use the same viscocity scale, so take it for what its worth.
Synthetic vs non-synthetic should not be your first criteria for the ZF6. You'll probably find that although harder to come by, the GM fluid is preferred. Testing by ZFdoc and experience from myself and some forum members, raises doubts about the use of the Castrol synthetic TWS 10-60 motor oil.
You have the wrong attitude.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by corvetteronw
I'm home now. Here is the text from Chris Petris' C4 class that I took last year: 6-speed transmission. Drain the transmission. A large 14mm Allen wrench is necessary. Remove the fill pulg.
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From: Rolla Missouri
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St. Jude Donor '10 thru '25
Originally Posted by CentralCoaster
You will need a 17mm allen wrench, not a 14mm. Check Autozone for a 3-pack containing it that fits on your 1/2" ratchet.
I just purchased the 3 pack last weekend. 17mm is what it takes.
Also bought the little plactic pump. Very hard to add the fluid in a ZF6 without one, since the fill plug is on the side.
And to Runemaster, Do what CentralCoaster says......... you buy 3 quarts of trans fluid and it will take approx. 2 1/2 quarts before it starts running out the fill hole. I used Amzoil, it lists the GM spec on the bottle. The type of fluid you use is up to you, as the orginal GM part number is no longer available or at least very hard to find. This topic has probably been discussed on this forum more than any other. And every brand/type of fluid has it's supporters and nay sayers.
One final note: Be sure and get your car up high enough to climb under and make sure it's level too. If it's not level, you will not get an accurate measure when adding the new fluid.
Team Owner
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
To my knowledge, I haven't heard of ZFdoc questioning Castrol TWS fluid for the man trans. Please show references for this.
This is from ZFdoc.com, FAQ section:
"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 superceded 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. ..."
They did their own (ZFdoc, did) test and concluded the following:
" 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."
This is from ZFdoc.com, FAQ section:
"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 superceded 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. ..."
They did their own (ZFdoc, did) test and concluded the following:
" 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."
Last edited by AORoads; Jul 7, 2006 at 10:16 PM.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by LT4CompYell
To my knowledge, I haven't heard of ZFdoc questioning Castrol TWS fluid for the man trans. Please show references for this.
Originally Posted by from ZFdoc website
(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 superceded 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.
(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 superceded 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.
Drifting
Joined: Sep 2003
Posts: 1,483
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From: middle TN
Auto instructor at the tech school where I used to work recommended Mobil 1 5w30 for the ZF. That was 30K miles ago. Drained it early this week and it still had that nice caramel color, tranny shifts smooth, quiet, everything good. I re-filled with Mobil 1 again because it's available and seems to work great. Car has 54K miles total.
Another point: ZFdoc says something like 85% of the units that come into his shop are the result of poorly functioning clutch hydraulic systems that damage the trans...not poor lubrication.
I re-filled with Mobil 1 again because it's available and seems to work great. Car has 54K miles total.Another point: ZFdoc says something like 85% of the units that come into his shop are the result of poorly functioning clutch hydraulic systems that damage the trans...not poor lubrication.
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
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From: King George VA
Originally Posted by Runemaster
I need to change my manual trans and rear diff fluid. Anyone know what type and how much fluid goes in each? It's a '96 LT4 6-speed with 3:45 rear gears.
AMSOIL Synthetic Synchromesh Transmission Fluid (MTF)
The differential takes 1.7 quarts of 80w90. The limited slip diffs also uses 4 oz of GM part no. 1052358. This AMSOIL product meets these specs and it comes with the friction modifier included so adding the 4 oz of modifier is not normally needed. I use this fluid in my 2002 Z06 and don't need the modifier.
AMSOIL Severe Gear Extreme Pressure Synthetic 75w90
This comes in handy for those doing it themselves: AMSOIL Hand Pump
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