SCorvette08

Help me with the best way to go about replacing the rear End oil and M7 trans oil
Im hearing Redline ,Royal purple, GM ect . what is the best brand and i'm at 11,000 miles so should i get the oils changed thanks

iridelow

NO....Only 11k, the car should be well over 60K before you mess with gear oils!

juanvaldez

Not true. I've already changed differential with GM gear lube I got from Amazon. Folks a Ron Fellows recommend early change. There is some kind of break in lube from the factory. I haven't changed trans fluid.

speedlink

NO! The oil needs to be changed at 500 miles on dry sump engines. That's it.

speedlink

Have you read the owners manual? That will tell you change intervals. Way too early for the rest of the fluids. But you can do as you wish.

B&BVettes

INCOMING!!!!

Pete43

I changed my differential oil at 17k miles and it looked like a silver gray sludge. Nothing like the oil that goes back in. I don't track my car. I would recommend changing the dif oil early the first time.

juanvaldez

Yeah, what would those dummies at Spring Mountain know?

BJ67

Synthetic Mobil 1 75-90 LS for the rear (non elsd) and synthetic amsoil torque drive for the M7 trans.

Greg00Coupe

I checked the rear in on my 14 before I was going to trade it and it was ugly at 18 K miles. On my 16 I changed it at 5k miles and there was crap on the plug and it was getting discolored. You cant go wrong changing fluids. And its very easy.

domenic tallarita

I think I posted this before, but I bought every rubber boot on my C2 fire wall, clutch arm, shifting, and new emgcy brake cables to get the rubber ends. The car has not been started or out of the shop.
All the rubber crumbled. I re ordered the shifter boot and the rubber was cracking when I opened the box!

Dom

devnull

I typically change the diff at 2k miles, and the transmission over to Redline D4 before 10k. Neither are mandatory but even with 2k that diff gets pretty nasty and it's easy to do.

Trans is really not needed unless you prefer the different fluid. At 11k it's not like you HAVE to change the diff fluid, but I do and would if it were my car.

domenic tallarita

Sorry about posting in the wrong thread.

Dom

NortonCO

Both tasks are easy to do and, while neither is "required" yet, changing early and/or more often won't harm anything. Many would argue it's good to replace "break-in" lubricants sooner, rather than later.

​​​​​​As with the basic question of whether to change, asking about brands will net a variety of responses. You won't go wrong using what's recommended in the Owner's Manual. Some, including me, believe better quality lubricants are available.

FWIW, I replaced all the lubricants in my '19 Z06 with Amsoil - engine oil @ ~500 miles, transmission and diff fluid/oil @ ~1500 miles.

Mad*Max

Is the differential oil nasty only on the first change or every subsequent change?

Jaykoh-Z51

My experience, it was funky at each fluid change.

Mad*Max

that's interesting, thanks for the info

mdformula350

I went with ac delco factory replacement fluid for both, just need to find the time to replace now. found a great deal and saved like 50 bucks on 4 quarts of each.
after alot of back and forth it seems both work well overall.
i doubt either have been changed and or checked since new and at about 22,500 miles.

hisvett

If you are tracking your car, by all means, change the oils more often.....otherwise, use the schedule found in your car manual.

Major hint: when changing your rear diff, remove the rear sway bar caps and lower the bar out of your way. This will allow better access to the fill plug on electronic diffs.

enjoy the ride!

sgt1372

I change the oil/filter in all of my cars annually regarless of the mileage.

However, the C7 maintenance schedule recommends changing the AT/MT fluid at 45k mile intervals. I've only got 36k miles on the car now and at the rate I drive it (about 3k miles a year), I'm good for 3 more years. I'll change the diff oil at the same time.

I recently changed the AT/diff fluid in my BMW & MB, each at about 90k miles, when I bought them. Assume the fluids were never changed before then. The BMW/MB AT & diff fluid is supposedl good "for life" but the "recommendation" is to change them every them at least every 50/60k miles. So, I'm good for at least another 50k miles on each vehicle.

The transaxle fluid in my MR2 was changed in my MR2 at about 55k miles when an axle boot was replaced and the trans/transaxle and diff fluids were changed in my F250 at about 220k miles (abouth it w/200k on it).

This is just NOT something I'm **** about and have never had a problem as a result but it sound like a 50k mile interval between MT/AT/Diff fluid changes is perfectly reasonable.

BTW, out of the nearly 100 vehicles that I've owned/leased in my life, none of them ever had a trans/diff failure, whether I changed the MT/AT/diff fluids or not.