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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
With spring almost here finally I'm about to change my diff and granny fluid since it's never been done(30k miles). I'm curious what is everyones go to for these fluids and weights? It looks extremely simple to change both.
I like the Pennzoil Synchromesh. It got rid of my notchy 1-2 shift after a cold start and it shifts like butter when it gets hot. Plus, it's only $8 a bottle.
I used Amsoil severe gear 75W90 on the diff and Amsoil torque for the transmission, signature series 5W30 oil so I’m a bit biased to their products. They make good **** though, not cheap but good stuff, also added Amsoil’s slip lock with the gear oil.
Not sure about the diff fluid but I would go with AmsOil.
I do know that in my manual trans, the AmsOil Torque Drive has made if shift the smoothest and be the most consistent. And I have tried fresh OEM fluid, Redline, and Royal Purple. The AmsOil was/is hands down, the best.
In the Corvettes my Wife, the Fairest Sandra the Red, and I own, I've always used Red Line Shockproof Gear Oils in their rear drive axles and manual transmissions. I've used Shockproof products for almost 25 years. Our '71 Coupe has over 90,000 miles in it. Our C5 and C6 each have about 55,000 and our C7 has almost 15,000 miles. Obviously, we never had any lubricant-related problems with drive axles or manual transmissions.
The Shockproof line is totally different from conventional petroleum gear lubricants and most synthetics because their viscosity characteristics vastly improved. The teeth in hypoid drive axle gearsets and those in helical gear manual transmissions require high viscosity at high temperatures to prevent metal-to-metal contact and low viscosity when cold to reduce fluid friction.
The chemistry of ShockProof products reduce high temperature thinning, thus reducing wear during severe duty use. They also have a coefficient of friction that's nearly half that of a conventional gear oil. Those properties combine to offer temperature reductions of 25-75°F in race track or high-performance street use.
The Shockproof gear oils' unique formulation allow them to lubricate like high-viscosity gear oil but flow like a lower viscosity product. For example, Heavy Shockproof can be rated as an SAE 75W250 gear oil, but has the fluid friction of a 75W90. LightWeight Shockproof can be rated as a 75W140 Gear Oil, but has the fluid friction of an SAE 30 motor oil. SuperLight Shockproof rates as a 70W90, but has the fluid friction of an ATF.
ShockProof Gear Oils provide greater viscosity in the thin layer of lubricant between gear teeth, but have very low internal fluid friction which means less power loss for the reliability and durability achieved.
Under moderate loads, such as high-performance street use, the Shockproof gear oils can reduce wear by as much as a factor of 10. Under heavy loads, such as racing in hot weather, compared to petroleum-based gear oils, the Shockproof products can reduce wear by a factor of three and, compared to most other synthetic gear lubricants, by a factor of two.
Two real-world demonstrations of the value of the Shockproof chemistry's ability to lubricate the extreme pressure regions of gear systems are Top Fuel drag racing and off-road truck racing. Both these types of motorsports apply severe shock loadings to drive axles. Red Line Heavy Shockproof Gear Oil is the choice of most leading race teams which compete in them. In fact, the original Heavy Shockproof formulation came from off-road truck racing as a way solve drive axle failure due to the driveline shock loading which comes when race trucks get airborne, suddenly unloading, then abruptly reloading their drivelines.
In my Corvette rear drive axles, regardless of differential type–I use Red Line Heavy Shockproof. "HSP" also has a friction modifier blended into it so, in limited ships which are in good condition no limited-slip "additive" is necessary.
In transmissions originally designed for high-viscosity gear lubricants, such as the Muncie four-speeds of the muscle car era or older aftermarket transmissions like the Richmond four, five and six-speeds, I use LightWeight Shockproof.
In modern manual transmissions such as the T56 or TR6060s used in C5/6/7 Corvettes, I use the SuperLight Shockproof and, in both those types of six-speeds, I noted a nearly immediate improvement in shift feel and a reduction in shift effort.
I used Amsoil severe gear 75W90 on the diff and Amsoil torque for the transmission, signature series 5W30 oil so I’m a bit biased to their products. They make good **** though, not cheap but good stuff, also added Amsoil’s slip lock with the gear oil.
+1 here. I did my oil last night, tranny tonight and will do diff tomorrow. All Amsoil. Had it in my C5 Z and it was great.
I just took my car out for a quick drive to do some figure 8's for the diff fluid. I have to say I am impressed with the amsoil transmission fluid. My second gear was always notchy when cold and today it was smooth as butter.
I just took my car out for a quick drive to do some figure 8's for the diff fluid. I have to say I am impressed with the amsoil transmission fluid. My second gear was always notchy when cold and today it was smooth as butter.
I had the same experience when I changed mine, stuff works very good.
Curious...I also run Amsoil Torquedrive and rear gear oil. But I went with the 75W-110 severe gear oil (w/ sliplock)...does anything think that the additional 20 degree rating will cause issues? Thus far, it hasn't.
Sorry for bringing this topic up again, can I use the Torque drive ATF on my manual transmission? Im looking to change the oil out on my trans/diff this winter, so any suggestions you guys might have will definitely help! Thanks in advance.
Sorry for bringing this topic up again, can I use the Torque drive ATF on my manual transmission? Im looking to change the oil out on my trans/diff this winter, so any suggestions you guys might have will definitely help! Thanks in advance.
03-19-2019, 08:00 AM
Diff and tranny fluid
