Diff, tranny, brake fluids

[rumatt]

Anyone have recommendations for diff, tranny, and brake fluids for my 330? It's 2.5 years and has stock diff and tranny fluids.

I'll be doing a few track schools and a crap load of autoxs. Figured changing all the fluid doesn't hurt.

For brakes I might do Motul 600, but some say it's overkill. I'd almost prefer something that lasts a bit longer.

Many love redline for diff / tranny. Others say it's not good for tracked vehicles. :scratch:

[Plaz]

When I finally get around to changing my tranny fluid, I'm going with the OEM MTL-2 stuff.

[rumatt]

When I finally get around to changing my tranny fluid, I'm going with the OEM MTL-2 stuff.

Any particular reason why? What have you read about it? Even for track use?

[bren]

Use the MTL-2 for the tranny and the OE diff fluid also. Redline is crap, I'd use Royal Purple or AMSoil if you want to go aftermarket.

I use Valvoline SynPower for brakes. It has nearly the same boiling point as ATE and is less hygroscopic.

[rumatt]

Redline is crap

Uh oh alex... You might want a fluid change.

Brakes too. They soft yet?

[BahnBaum]

Uh oh alex... You might want a fluid change.

Brakes too. They soft yet?

They feel fine, but I'll do a flush when I put the new pads on.

Alex

[rumatt]

Good link from Brendon: http://www.volvoclub.org.uk/faq/BrakeFluidComparison.html

[John V]

I had redline in my RX-7 after I blew out the first trans. It was an 80,000 mile used tranny in a 90,000 mile chassis and I sold it at 120k, after two fluid changes. The redline really quieted down the bearings of that trans, which had been extremely noisy. That car saw a lot of heavy track time. Each time I changed the fluid it came out very clean, and there were very few metal flakes on the magnetic drain plug.

I've used redline in each of my cars and it's treated me very well. Amsoil didn't work in the SHO - it made the shifting way too notchy. Went back to redline and everything was happy again.

I personally don't think the fluid makes nearly as much difference as how often you change it does.

The Boxster will be getting redline as soon as it warms up.

[Pinecone]

I have MTL-2 in the E46 and OEM in the diff.

Both the LTW and the Roadster have Redline in tranny and diff. MTL in the trannies and the standard stuff for the diff (75W-90???). I may go to Mobil 1 in both next change. Bob Tunnell ran all Redline, but had to put Mobil 1 (cuoldn't get Redline in time) in the diff and found his diff temp went down about 20 degrees.

[rumatt]

I have MTL-2 in the E46 and OEM in the diff.

Bump.

I'm thinking of going this approach. Will the dealer sell me these if I walk in, or do I have to bribe them or something (being that they're "lifetime" fluids and I shouldn't be changing them).

[operknockity]

Bump.

I'm thinking of going this approach. Will the dealer sell me these if I walk in, or do I have to bribe them or something (being that they're "lifetime" fluids and I shouldn't be changing them).
The MTL comes in 5 gallon jugs, so find a couple of friends who want to all do the tranny fluid. Not sure about the diff fluid.

I was figuring on Royal Purple for both the tranny and diff when I get around to doing it.

[rumatt]

The MTL comes in 5 gallon jugs, so find a couple of friends who want to all do the tranny fluid. Not sure about the diff fluid.


Ugh.. Screw that. I might just do royal purple.

Thanks for the info.

[Pinecone]

Uum, 5 LITER jugs. Which will do 3 changes at a cost of about $120.

[Nick M3]

Uum, 5 LITER jugs. Which will do 3 changes at a cost of about $120.
(2 E46 M3s and 1 E46, or 4 E46es.)

[Doug]

Stick with the stock fluids, you'll be fine even with light to moderate track use

[Nick M3]

Stick with the stock fluids, you'll be fine even with light to moderate track use
Stock fluids hold up better under track use than anything else.

[John V]

Incidentally, my old '95 M3's diff was sent off to diffsonline by the new owner so it could be rebuilt. This diff has had redline in it since it was 28,000 miles old, and is now at around 80,000 miles, with a bunch of hard autocrossing and some track days mixed in.

And the diff inside is reported to be "sparkling clean, like new" on the inside, with almost no clutch or bearing wear (except the input shaft bearing, which was overtorqued and toasted) and no noticable gear wear.

[Nick M3]

No, he sent it to Blanton. Diffsonline doesn't like redline.

[Plaz]

Ugh.. Screw that. I might just do royal purple.

Thanks for the info.

We could work something out... I still need to do this.

Wanna split a jug? That way we're only each buying twice as much as we need, instead of 4 times as much. :dunno:

[John V]

No, he sent it to Blanton. Diffsonline doesn't like redline.

You're wrong. It was sent to Diffsonline. But regardless, Dan has no idea it was run with Redline.

Now, Jason got his new differential from Blanton. Maybe that's what you're thinking of. Jason sold the factory 3.15 diff to Bogdan and that's the one getting rebuilt.

[Nick M3]

You're wrong. It was sent to Diffsonline. But regardless, Dan has no idea it was run with Redline.

Now, Jason got his new differential from Blanton. Maybe that's what you're thinking of. Jason sold the factory 3.15 diff to Bogdan and that's the one getting rebuilt.
I still don't regard that as a useful comparison, though. You never tracked it, so far as I know and Jason dooesn't actually use the skinny pedal out on track. Ergo, the diff was never really heated up. (Autoxing does not count here.)

[John V]

I wasn't trying to make a comparison. :dunno: Just giving another datapoint. My RX-7 saw more track time than both of your cars put together and never had any problems with the trans and diff. There's a ton of internet folklore out there about various fluids, believe what you want I guess.

[Doug]

Stock fluids hold up better under track use than anything else.

That's why race cars run stock fluid right? :rolleyes: I'm not going to get into the fluid debate with this group.

[Plaz]

the fluid debate

http://freemasonry.bcy.ca/fiction/other/dr_strangelove.jpg

[iateyourcheese]

http://freemasonry.bcy.ca/fiction/other/dr_strangelove.jpg

Great reference. One of my favorite movies ever.

Back on topic: I filled my transmission with Redline this weekend and I'm happy with it. It shifts about the same when warm, but gone is the resistance when it's cold.

[bren]

That's why race cars run stock fluid right? :rolleyes: I'm not going to get into the fluid debate with this group.
Sponsorships and contingencies can sway many racer's choices.

Besides, fluids in race cars are changed at significantly shorter intervals than road cars (especially if they use Redline :p)

[rumatt]

OK, weird.

I just got off the phone with the parts dept. at my local BMW dealer. He told me the following:

1) He sells only 5 gallon jugs of the tranny fluid, and it's $510 for 5 gallons. He's never seen a 5 liter container of it, but if I have a part number he'd like to know because he's curious

2) He said that I should NOT be doing this unless I know what I'm doing. There's a special procedure for changing the fluid where you need to get the temperature of the fluid right before putting it in, or you won't get the right amount. It's a fairly difficult procedure that controlled by the computer to monitor the temps of the fluid in the tranny, and the incoming fluid (or some shit like that).

I tried to get him to explain why late model BMW's are so special, and he admitted he wasn't quite sure why, but basically said that BMW created a mess, and that unless you really know what you're doing you CAN make it worse than just leaving the lifetime fluid in there.

:dunno:

[Nick M3]

83 22 0 309 031

I've heard that they may have released LT3, so that part number could be out of date. He shoudl be able to find what replaced it, though.

As for the temperature of the fluid, I haven't yet heard of anyone doing that. So ignore it.

[John V]

I tried to get him to explain why late model BMW's are so special, and he admitted he wasn't quite sure why, but basically said that BMW created a mess, and that unless you really know what you're doing you CAN make it worse than just leaving the lifetime fluid in there.

:dunno:

It sounds like he thought you had an autotragic, or (even worse) an SMG.

Until a manufacturer offers me a "lifetime warranty" on my transmission or diff, I'll continue to replace their "lifetime fill fluid" with Redline at 30k intervals. :)

[operknockity]

Uum, 5 LITER jugs. Which will do 3 changes at a cost of about $120.
Ooops. Yes. Thanks for the correction. The upshot, though, is the same.... The smallest quantity you can buy is way more than you need for one car.

[rumatt]

As for the temperature of the fluid, I haven't yet heard of anyone doing that. So ignore it.

Everyone replaces with room temp fluid? Drain warm, fill cool?

If the BMW tech's have a complex proceedure with temperature controlling requirements, that is slightly troubling though.

(BMW Tech, you have any info on this?)

[Nick M3]

Everyone replaces with room temp fluid? Drain warm, fill cool?

If the BMW tech's have a complex proceedure with temperature controlling requirements, that is slightly troubling though.

(BMW Tech, you have any info on this?)
uh.

read the number i posted. :p

[bren]

So he's saying that the density of oil changes as it's heated? :?

[Doug]

So he's saying that the density of oil changes as it's heated? :?

It's called Viscosity, what do you think 10W40 means?

http://www.autoeducation.com/autoshop101/oil-change.htm

[bren]

It's called Viscosity, what do you think 10W40 means?
I understand viscosity...which is much different from density. Maybe I should have said volume.

I'm trying to figure out how you are not able to get the proper amount of oil in the diff/trans. I don't see how it matters if it flows like water or molasses if all you do is fill it until it runs out the drain plug.

[rumatt]

So he's saying that the density of oil changes as it's heated? :?

Not impossible. :dunno: Although I guess temperature usually doesn't affect the density of liquids substantially (like it does with gas).

Maybe the guy's a total tool, but I'd be curious to hear the BMW procedure before assuming it's total BS.

[Rob]

Are you guys serious? You check your oil when it's warm b/c . . . right, b/c it expeands. Although there is a lot less tranny fluid in a manual transmission than 5 quarts, the principle would be the same. In automatics, it might be enough volume to make a difference.

I haven't thought about it, but I wonder if I should change the tranny fluid in the station wagon. It's getting close to 50k. Hmm. It certainly hasn't ever seen a track.

[iateyourcheese]

Not impossible. :dunno: Although I guess temperature usually doesn't affect the density of liquids substantially (like it does with gas).

Maybe the guy's a total tool, but I'd be curious to hear the BMW procedure before assuming it's total BS.

No kidding you guys. Density also changes with temperature. Coolant is probably the most striking example in the car.

So maybe BMW is warning about any sort of overfilling. If you fill when cold it has the ability to expand and wreak havoc.

Maybe you can fill it cold, drive it to warm it up again, and then crack open the fill bolt to remove any overfill? Or get some crazy warmer for your fluids.

[John V]

The transmission and all its internal parts are pretty massive, and everyone drains with the trans cold. My guess is the trans case and all its internal bits will have no problems briging the new fluid up to a very high temperature pretty quickly.

If not, the fill -> drive -> check level procedure should work just fine.

John

[Pinecone]

Auto trannies do get checked with a dipstick when at operating temp. But they also hold something like 8 - 11 quarts (torque converter holds a BUNCH). And the difference is less than a pint. So in a manual, with half the fluid or less, you are looking at a couple of ounces difference. And guess what, you will OVERFILL by filling cold, no underfill.

But when they did the 1200 miles service on my M3 they did not heat, warm, cool, or do anything with the tranny fluid they put in. Drained and filled out of a room temp container. Same with the diff.

[John V]

And guess what, you will OVERFILL by filling cold, no underfill.

I think that's what everyone is saying.

[rumatt]

you will OVERFILL by filling cold, no underfill.

Sure.. Now the question is.. does that (likely small) amount of overfil matter....

I'm guessing not really.

[operknockity]

Sure.. Now the question is.. does that (likely small) amount of overfil matter....

I'm guessing not really.
Most of the SoCal tribe have been doing warm/hot drain, cold fill for years with Red Line and MTL/MTL2 and have not had any problems. If the diff/tranny is still hot enough when you start the fill, it'll probably warm up the new fluid pretty quickly so that you don't get a cold overfill situation.

[John V]

Most of the SoCal tribe have been doing warm/hot drain, cold fill for years with Red Line and MTL/MTL2 and have not had any problems. If the diff/tranny is still hot enough when you start the fill, it'll probably warm up the new fluid pretty quickly so that you don't get a cold overfill situation.


Is there an echo in here? :D

[operknockity]

Is there an echo in here? :D
Could be. :beatdeadh

[nate]

fyi - I boiled Redline MTL back in 2004 while doing 150mph or so. I would recommend the factory stuff.

[Plaz]

We could work something out... I still need to do this.

Wanna split a jug? That way we're only each buying twice as much as we need, instead of 4 times as much. :dunno:

Gotta rescind the offer. I just said "f it" and put in Redline D4 ATF today.

Was also fortunate enough to get some splashed in my hair due to a wonky hand-pump.

The old fluid was pretty nasty looking, after 85K or so. :ack:

[rumatt]

Gotta rescind the offer. I just said "f it" and put in Redline D4 ATF today.

Shit. I never saw your original post until now anyway. :lol:


I'm reading this saying, "what offer?" :scratch: