jtswenson

Hi Folks,

Just bought a 2011 Zr1, and I'm planning to change all the fluids.

First, is the transaxle all in one, or are there separate drains and fills? What would you guys recommend for heavy track use?

Second, without starting WWIII, what oil would you guys recommend for heavy track use?

I don't plan to street drive the car much, and I won't be turning laps for long periods of time, but I do plan to run a road course near me and some autocross and a little bit of street driving.

Thanks in advance!

SweetZO6

Yeah, I've had my '10 for a year and I do all street driving. I use Royal Purple 5W-30 HPS motor oil with a K&N re-useable oil filter. I want to change the tranny fluid to RP Snychromax and RP 75W-90 gear oil in the diff. I assume the tranny has fill and drain plugs but the diff is what confuses me. Are there fill and drain plugs or do I have to remove the diff cover to drain fluid? I have a friend that has a real nice car pit. Makes it easy to get under the beast . I would like to know what is needed to do the job. Any help would be appreciated.

Ed

froggy47

You cannot go wrong with Redline, everything.

UrbanKnight

This... ALL of THIS..

I run redline everything...

weight of oil depends on your climate, I run 40wt straight on my Zr1 down here in FL....

GOLD72

The tranny has separate Fill and Drain plugs on opposite sides of the housing. The Diff has a Fill plug that faces rearward in back of the right side muffler. The Diff drain does not have a separate dedicated drain plug. The Diff is drained via disconnecting the circ pump inlet line from the bottom rear of the housing via a quick disconnect wire spring clip. Same clip that GM uses elsewhere on vehicle hydraulic lines. Having a spare clip is a good idea. Shop manual I believe recommends that you install a new one when reassembling the connection. I have not done a diff fluid change on my ZR1 yet but have done it previously on a 06Z years ago which is very similar. Just a standard 3/8" drive socket ratchet wrench and a hand pump for refilling the housings with fresh fluid. A small flat blade screwdriver for prying the spring clip out.

GOLD72

Entirely separate and different fluids. The Tremec tranny uses a DEXRON III ATF fluid or similar meeting DEXRON III. Do not use the fluid if labeled that it meets DEXRON VI. DEXRON 6 can be used in autos but not the Tremec manuals. 75W90 is the differential gear lube to use. DEXRON LS is highly recommended for corvette differentials and has been factory fill since MY2009. If you want to use an aftermarket fluid, I have had great success with AMSOIL Severe Gear 75W90 with some additional additive in resolving slow speed chattering on two pre-2009 vettes.

whatcop?

Same fluids I use

SweetZO6

Gold72, many thanks for the info.

Ed

GOLD72

Just completed my diff fluid change. My 2011 ZR1 required a 10mm hex head (Allen) socket for the FILL plug. I seemed to remember my 06Z06 only using the square end of a 3/8" drive socket wrench or socket extension for the FILL plug.