BG Syncroshift 2

[kennyfrc]

I just picked up a 2008 Z4MC and swapped out the OEM Trans fluid for this and it worked wonders to reduce shift effort. Never tried syncromax so I can't compare.

[Shipkiller]

I put RP Syncromax in about two weeks ago. I agree, big difference.

[r4gs]

i'm interested in getting a smoother shifter feel. how much time does it require to change the transmission fluid on the m cars?

[a_riddler]

15 minutes after you get the car on jack stands. Super easy, just make sure to get a short 8mm 3/8th allen socket. Its pretty tight to get to the fill plug with a standard length socket, but doable.

http://www.zpost.com/forums/showthread.php?t=79739

This guide works, just substitute the 8mm socket for the 14mm wrench. Takes 1.6 Qt (1.5 Ltr) and torque to 26ft/lbs.

I went with RP Synchromax and did notice cleaner shifts.

Also did the diff with RP while up on the jack stands.

[kennyfrc]

Originally Posted by a_riddler

15 minutes after you get the car on jack stands. Super easy, just make sure to get a short 8mm 3/8th allen socket. Its pretty tight to get to the fill plug with a standard length socket, but doable.

http://www.zpost.com/forums/showthread.php?t=79739

This guide works, just substitute the 8mm socket for the 14mm wrench. Takes 1.6 Qt (1.5 Ltr) and torque to 26ft/lbs.

I went with RP Synchromax and did notice cleaner shifts.

Also did the diff with RP while up on the jack stands.

I thought about trying redline fluid in my diff. Is all they hype about the OEM fluid valid?

[Shipkiller]

Originally Posted by a_riddler

15 minutes after you get the car on jack stands. Super easy, just make sure to get a short 8mm 3/8th allen socket. Its pretty tight to get to the fill plug with a standard length socket, but doable.

http://www.zpost.com/forums/showthread.php?t=79739

This guide works, just substitute the 8mm socket for the 14mm wrench. Takes 1.6 Qt (1.5 Ltr) and torque to 26ft/lbs.

I went with RP Synchromax and did notice cleaner shifts.

Also did the diff with RP while up on the jack stands.

Just make sure you loosen the 'Fill' plug first.. If you can't get that one off, the don't even think about the drain plug...

[r4gs]

how likely is a change of transmission fluid, especially the thinner rp synchromax, going to affect transmission wear? i'd be concerned about warranty issues, since i'm under cpo for the next two years. car only has 15,200 miles right now.

also, how much transmission fluid do we need to do a full swap? apparently, i've read that i should take it in to a proper transmission shop and have them connect a pump machine that will drain all the old fluid while pumping in all the new fluid?

[AWM3]

Originally Posted by r4gs

how likely is a change of transmission fluid, especially the thinner rp synchromax, going to affect transmission wear? i'd be concerned about warranty issues, since i'm under cpo for the next two years. car only has 15,200 miles right now.

also, how much transmission fluid do we need to do a full swap? apparently, i've read that i should take it in to a proper transmission shop and have them connect a pump machine that will drain all the old fluid while pumping in all the new fluid?

You are confusing manual transmissions with automatics. The Z4M manual transmission holds 1.6 quarts and every bit of it will come out if you open the drain plug on the bottom. No special procedures necessary. As for warranty issues, with the transmission oil that's a very fuzzy area because not even all dealers will agree which manual transmission oil to use - some will use LT2 and some LT3. In any case it would be difficult to demonstrate that your transmission failed because you used a different brand of high quality synthetic gear oil if it met the same specifications.

[kennyfrc]

They only way they'll know you changed it is if you tell them.

[007MCoupe]

Originally Posted by Shipkiller

Just make sure you loosen the 'Fill' plug first.. If you can't get that one off, the don't even think about the drain plug...

speaking from experience? sounds like something I would do...

How often do you all change yoru fluid? I've driven mine 5K since May and Inspection 2 is 5K away. Would it even be worth it to change it out before then?

[r4gs]

i'd wait till inspection 2, since transmission and differential fluids will be changed for sure. u could probably ask the tech to fill with an aftermarket transmission fluid of ur choice, but the stock fluid is pretty good and should be no problems. aftermarket transmission fluid can typically last through more than 20,000 miles. bmw's oem lt2 transmission fluid is supposed to go 50,000 miles or so, hence the replacement at inspection 2.

[007MCoupe]

that's what i was thinking, just didn't know for sure. this is the first car i've owned from a dealer with a warranty.

[r4gs]

alright, ordered myself two liters of rp synchromax off amazon + free shipping. good deal. is there something i should take note of the fill and drain bolts? i understand they can be mighty easy to strip bare and then it becomes almost impossible to remove. my concern would be bolting them back on though, will they seal sufficiently?

[dekaliber]

FWIW, my mechanic's opinion was that the only downside to BMW's tranny fluid is its expense. As far as gear protection, it's supposed to be pretty top notch. He told me that the fluid he drains out of cars with 100+K miles often looks cleaner than cars with aftermarket fluids after much fewer miles.

In the end, I guess it comes down to risk. There's a theory that the fluids that improve shifter feel are actually thinner and that's the mechanism by which resistance is reduced. Whether they provide adequate long term protection of the gears is anyone's guess. If you do change fluids, I'd get a Blackstone analysis of your OE fluid after you drain it, and then get another analysis of the aftermarket fluid after a similar mileage interval. I'm personally curious to see the result.

In the meantime, since I don't ever see myself getting rid of this car, I decided to go the safe route and returned the 2 bottles of RP Synchromax I had ordered from Amazon. My transmission is on the notchy side for sure (especially comparing to the ZHP, which has an identical ZF unit I believe) but it's not so bad that it's grinded or gotten in the way of some very entertaining driving.

Btw, it's recommended that you get new drain cover bolts since they're supposed to be single-use.

[a_riddler]

Passing along the info from Ron Stygar:

Transmission plug: http://www.bimmerfest.com/forums/sho...04&postcount=1

Differential plug: http://bimmerfest.com/forums/showpos...33&postcount=1

The plugs are not reusable, as they have crush washers on them. Ordered mine through Tischer.

[r4gs]

thanks for the links to the relevant part number. i will wait and see regarding the actual fill and drain plugs themselves and if they're fully sealable and reusable again with new crush washers. seems like a few zposters have swapped out their tranny fluids without replacing these bolts, and have not had any leaks to speak of.

[a_riddler]

I just replaced the drain plug and re-used the fill plug without any issues, but that was simply because I didn't think to order two..

The part is cheap, I will order both the drain and fill plugs for next time.

[r4gs]

my two bottles of rp synchromax just shipped, should arrive by late next week. will report with how my shifter feels after.

[AWM3]

Actually the plugs have 0 rings, not crush washers, and I think as much as anything they should be replaced because the allen socket is very easy to strip out if you are using cheap tools. Cheap meaning not Snap On or equivalent.

[Shipkiller]

I think the O-Ring plugs are for older cars. Not sure.

My 08 has crush washers, and the new ones I ordered were also crush washer.

+10 for the cheap tools comment.

[r4gs]

going to take extra precaution regarding the use of proper tools. i've read about inadvertently stripping the bolts and the huge pain to have them removed thereafter!

[onebluemcm]

Originally Posted by dekaliber

FWIW, my mechanic's opinion was that the only downside to BMW's tranny fluid is its expense. As far as gear protection, it's supposed to be pretty top notch. He told me that the fluid he drains out of cars with 100+K miles often looks cleaner than cars with aftermarket fluids after much fewer miles.

In the end, I guess it comes down to risk. There's a theory that the fluids that improve shifter feel are actually thinner and that's the mechanism by which resistance is reduced. Whether they provide adequate long term protection of the gears is anyone's guess. If you do change fluids, I'd get a Blackstone analysis of your OE fluid after you drain it, and then get another analysis of the aftermarket fluid after a similar mileage interval. I'm personally curious to see the result.

In the meantime, since I don't ever see myself getting rid of this car, I decided to go the safe route and returned the 2 bottles of RP Synchromax I had ordered from Amazon. My transmission is on the notchy side for sure (especially comparing to the ZHP, which has an identical ZF unit I believe) but it's not so bad that it's grinded or gotten in the way of some very entertaining driving.

Btw, it's recommended that you get new drain cover bolts since they're supposed to be single-use.

Type of trans fluid was/is a hot topic for debate in the E46 M3 forums as well. Seems like one general consensus opinion from the more experienced people over there is that if you do switch to a lighter weight fluid, you are comitting youself to changing it more often than with the BMW recommended fluid if you want to avoid fluid breakdown and wear problems. I think they were saying every 15k miles to be sure you don't have problems, but I haven't looked at those threads in a while. I was going to do trans fluid in my '04 M3 b4 I sold it since it had about 50k miles on it, but I decided not to because I couldn't decide what fluid to use and figured I'd be better off letting the new owner decide what he wanted.