Should I change "Lifetime" transmission fluid? or is that a bad ide?

[benhenny]

I have a 1998 Z3 2.8 manual transmission with 112k miles that has never had its transmission fluid changed, as far as I know. As I understand it, the transmission has "Lifetime" oil in it - is that correct? As much as I'd like to believe in its longevity, I think I'd sleep better if it had the fluid changed.

I've read here and elsewhere that changing the fluid helps the notchiness that I feel when I shift. Going from 3rd to 4th, I often feel a notch as I shift all the way down, causing not such a smooth and fast shift motion. It's always bothered me - I've had it for 6 years.

Last week, I had a good transmission place check it out, and they couldn't find anything wrong with transmission. So I'm thinking of changing the transmission fluid (oil) to see if that would help.

Should I bother changing the fluid if it's supposed to be "Lifetime"?

Thanks!

[Bear Grylls]

Amsoil MTF

will change your life

[z3540i]

"Lifetime" for bmw meant the "Lifetime" of the lease/warrenty....Change the fluid and then change it every 30k ish miles after that....I run Castrol synthetic ATF in mine but i swapped the transmission from a 93 318 so im sure others will comment on the type of fluid to use....

Cliff Notes
* CHANGE YOUR TRANSMISSION FLUID
* DONT FORGET ABOUT THE DIFFERENTIAL ALSO

[CodyR]

I have a 98 2.8 too. Mine has 178k on it. I changed to Royal Purple Synchromax at 30k and have changed it every 30 - 40k since. It made an immediate positive difference in the shifting when I switched at 30k.
You might also consider changing your diff fluid to Royal Purple 75W 90 Max Gear. I did that also at 30k, with 30 - 40k change intervals, and have had no problems at all. Royal Purple has been great for me. I highly recommend it.

[z3540i]

More Important i feel than What specific brand is that you get the right viscosity fluid and change it regularly

[benhenny]

Thanks! I wonder why my transmission guy didn't recommend changing the oil though.

I found a how-to here: h t t p://w w w.unofficialbmw.com/e36/drivetrain/e36_change_manual_transmission_fluid.html

Doesn't look too hard for someone with a lift. I'm still nervous about cracking into a sealed transmission...

More Important i feel than What specific brand is that you get the right viscosity fluid and change it regularly

What would be the right viscosity? In a given year, we have about 15 days between 20*F and 32*F and about 30 days of 100* - 110*.

[Cloudbase]

Hey man,

Def change it. The old school mx schedule interval is 60K miles.

I was using redline, but went back to BMW LT2 fluid for both diff and gearbox because I like the way it shifted better. You can get it at the dealer in .5 liter quantities. They are different fluids. Also the diff fluid should be for non-slip or LSD depending what your car has. If it's LSD there will be an S on the diff somewhere. Murray Motors stocks the fluids and will sell you a container too. 2 liters for both will be a few $$$, but it's worth it IMO.

I'll change it for you for a couple bucks. I'd say a case of beer, but I don't drink. Maybe a $20 starbucks card.

I'm in Superior. Should take about an hour. I have about .3 of a liter of BMW LT2 fluid you can have too.

[Telecomtodd]

Go to http://www.amsoil.com/ and "build" your car on the left hand side. Nearly all of the oils will be displayed along with certain notes. I didn't see MTF on the tranny list, curious if I would use that on my M Roady.

[z3540i]

Some manual Transmissions call for Gear oil like 75-90 and others use Automatic Transmission fluid... So i meant more so than brand its getting the right type.

* The transmission guy would rather sell you transmission and get installation than change your fluid.

*Its not Sealed its made to be changed...."lifetime"was a marketing scheme to pursuade buyers with lower maitenance cost...it was never about the actual health of the car just the buyers perspective of cost of ownership.

[Vintage42]

Thanks! I wonder why my transmission guy didn't recommend changing the oil though... I'm still nervous about cracking into a sealed transmission... What would be the right viscosity?...

The transmission guy was unfamiliar with the Z3 transmission(s). For instance, they take special automatic transmission fluid (an ATF called MTF), BMW thinks it will last forever, but lifetime fluid does not mean the transmission is sealed. Few mechanics are eager to change the fluid in a sealed transmission.

The transmission fluid is changed as usual, via a drain and fill plug. BMW makes a replacement fluid, as does Royal Purple, and AMSOIL. However, Royal Purple's SyncroMax MTF fluid is a transmission fluid, while AMSOIL's fluid is actually a 5W-30 motor oil. They both feel great, but I am not sure that the AMSOIL conforms to BMW specs for manual transmission fluid. The AMSOIL page for my Z3 says "No AMSOIL Product Recommendation" for the manual transmission.
http://www.amsoil.com/mygarage/Vehic...=1997+BMW+Z3+1

To change the manual transmission fluid, the car must be level and on the upper settings of jack stands. The plugs are washer-less and tapered, requiring high torque. The fluid must be pumped up into the fill hole, and there is little room around it. Buy a finger operated fluid pump at an auto store.

[CodyR]

Nothing to be nervous about. Just an 'old school' maintenance schedule, as Mike Miller would highly recommend in Roundel. It's easy to do and it's good for the car.
I live in Texas where the temperatures vary a lot. 100 degree summers, and a few days during the winter in the 20's and 30's.
The RP Synchromax is 10W. Get the RP Max Gear in 75W 90. That's the right viscosity... I can tell you from 178,000 miles of experience. :-)

[rf900rkw]

Just to clarify and demystify the conspiracy theories, it was not BMW that specified the lifetime fill, it was ZF. And GM. The idea being that the fluid is good enough to go the distance. What will hurt the fluid isn't breakdown, but rather contamination. And the oil will not get contaminated until the gearbox is failing... at which point changing the oil is a moot point.

As an example, GM specified the exact same change interval for the Z3 automatic that they did for your neighbors Malibu... none. The only difference is BMW advertised it.

For your manual, go ahead and change it. You won't hurt anything as long as you use the correct oil. Some here like the Amsoil. Others feel it's too thick. The "correct stuff", Pentosin MTF, is often available from NAPA. Or, some of us are running a sythetic Dex III ATF with excellent results.

[Telecomtodd]

I found Pentosin MTF2 at O'Reilly for $23 a quart. You can save a buck or so buying it elsewhere, but then you have to pay shipping. If I had two quarts shipped from O'R, the shipping charges were $13 more. I'd rather call the store and have them get it for me, no rush (yet).

[CodyR]

Benhenny - I have the same car as you, and none of the 98 2.8's have limited-slip diffs, so you don't have to worry about that.
Also, be careful of high torque on the tranny drain and fill plugs. They are tapered, but I recall reading a post somewhere where someone cracked their case by applying too much torque to tighten. Just tighten them up reasonably tight, like you would anything else. No need to strong-arm them.

[Bear Grylls]

Stock fluid for the transmission is 5w-30 I think
http://www.amsoil.com/shop/by-produc...n-fluid-5w-30/

I put in the heavier gear oil 75w-90 and could not be happier
http://www.amsoil.com/shop/by-produc...r-lube-75w-90/

This past weekend I think it got down to 15 degrees with freezing rain and snow, I was cruising around just fine. It is rather difficult to shift before the car warms up though

[z3540i]

Someone should post the actual torque spec in ft lbs...as i too overtightened it and had a hard time getting it back out.

I would say if it called for 5-30 and you put in 75-90 that doesn't seem like a good idea unless they were meant for 75-90 and bmw went thinner for eeasier cold shifts....

[z3540i]

sythetic Dex III ATF.

Bingo...my box is kinda whiney tho...sounds like straight cut gears in first and second lol fluid holds up good to abuse tho

[CodyR]

Nothing to be nervous about. Just an 'old school' maintenance schedule, as Mike Miller would highly recommend in Roundel. It's easy to do and it's good for the car.
I live in Texas where the temperatures vary a lot. 100 degree summers, and a few days during the winter in the 20's and 30's.
The RP Synchromax is 10W. Get the RP Max Gear in 75W 90. That's the right viscosity... I can tell you from 178,000 miles of experience. :-)

Get the RP Max Gear in 75W 90 for the Diff, that is...
RP Synchromax for the the tranny.... just to be clear.

[Cloudbase]

If I get around to it, I'll dig out the torques from the Bentley Manual. IIRC, there are crush washers for both, so the OP would need a total of 4.

Tech tip, always open the top plug first! So you know you'll be able to get new fluid in if the bottom one is overtightened.

[rf900rkw]

I'm showing 50nm. I personally think that's a bit high.

[Kenn]

Stock fluid for the transmission is 5w-30 I think
http://www.amsoil.com/shop/by-produc...n-fluid-5w-30/

I put in the heavier gear oil 75w-90 and could not be happier
http://www.amsoil.com/shop/by-produc...r-lube-75w-90/

That gear oil is NOT really a hugely different viscosity than 5W-30 trans fluid or motor oil. It's a bit more viscous, but not much. They are on different scales, inconveniently. I've posted the info multiple times, and seemingly everyone still believes that 75W-90 gear oil is really thick stuff compared to typical motor oils, etc. Again, they are not rated on the same scales.

For "proof," go here, about 1/3 page down:
http://www.syntheticwarehouse.com/motorcycle.htm

Or here, about 2/3 of the way down the page:
http://bbs.homeshopmachinist.net/thr...er-pick-an-oil

The same basic charts are in other places also. Also, gear oils reportedly have things in them that you may not want in your manual transmission that calls for a different fluid.

[spfd72]

Benhenny - I have the same car as you, and none of the 98 2.8's have limited-slip diffs, so you don't have to worry about that.

Fail. Check your facts before posting-especially if you are giving a noob advice.

[Bear Grylls]

That gear oil is NOT really a hugely different viscosity than 5W-30 trans fluid or motor oil. It's a bit more viscous, but not much. They are on different scales, inconveniently. I've posted the info multiple times, and seemingly everyone still believes that 75W-90 gear oil is really thick stuff compared to typical motor oils, etc. Again, they are not rated on the same scales.

For "proof," go here, about 1/3 page down:
http://www.syntheticwarehouse.com/motorcycle.htm

Or here, about 2/3 of the way down the page:
http://bbs.homeshopmachinist.net/thr...er-pick-an-oil

The same basic charts are in other places also. Also, gear oils reportedly have things in them that you may not want in your manual transmission that calls for a different fluid.

I know

I read through those before I got the gear oil for my transmission, just no one else seems to believe

[Vintage42]

Stock fluid for the transmission is 5w-30 I think
http://www.amsoil.com/shop/by-produc...n-fluid-5w-30/

I put in the heavier gear oil 75w-90 and could not be happier
http://www.amsoil.com/shop/by-produc...r-lube-75w-90/...

AMSOIL does not recommend the 5W-30 for BMW Z3. The AMSOIL product page says for Z3 says "No AMSOIL Product Recommendation" for the manual transmission.
http://www.amsoil.com/mygarage/Vehic...=1997+BMW+Z3+1
And if AMSOIL does not recommend their 5W-30 for the Z3, it is not like "stock" BMW fluid.

Putting heavy 75W-gear oil in the BMW transmissions which are made for thin automatic transmission fluids could lead to problems especially with shifting.

[z3540i]

This is a worse topic than "which motor oil do you use"