I have solved my 2nd gear cold synchro issue 110%
Basically, if I had the money I would treat all forum members to 3 quarts of this on my dime.
You would ALL offer to pay me back
and then buy me beers
yes plural why? :happy0180:
cause youre gonna buy 3 quarts of this
http://www.autohausaz.com/search/pro...er=83220309031
and then you too can be in aisin tranny NIRVANA, like me
read on to understand my method of oil choice, and really tho the proof is in the pudding.
This is BMW LL tranny fluid, its their factory lifetime fill, and its pretty high end stuff that goes into my M3
I have somewhat of a hobby with oils, and chemicals in general, my father is a chemist so maybe that helps you understand where I am coming from
changing fluids is easy, whats more interesting is the choice of fluids
page 51 of service manual lists MT gear oil as 75w-85 and diff lube as 75w-90
I found a few oils that are to spec:
the pennzoil syncromesh vs the pentosin MTF2 vs the redline MTL90 vs Castrol SMX-S
the correct kinematic viscosity of a 85 weight oil is somewhere between 7 and 14
SAE service level defines targets for a 75W gear oil to be= 4.1@ 100F and 7.0 based on that and the fact that folks using MT90 and folks using syncromesh by pennzoil are reporting better than MTL results
there is a rumor that the GM syncromesh IS pentosin, but I dunno
this led me to believe the MTL90 some guys on this forum may be my second choice so I did a little experiment that cost me $60
I dont put pennzoil in any of my cars
here is a list of their salient characteristics
penn synch * pentomtl 7580 * mtl90 7590 * smx-s
KV @100 * 9.08 * 7.7 * 15.6 * 11.9
KV @ 40 * 41.6 * 38.3 * 90 * 64.4
VI * 208 * 177 * 185 * 183
I dunno the weight of the syncromesh, and the smx is a 75w85
I had hoped better for the smx and the redline but they too are thick when cold
FAIL
SAE service level defines target KV for 75W gear oil to be= 4.1@ 100F and 7.0 based on that and the fact that folks using MT90 and folks using syncromesh by pennzoil are reporting better MTL results
see
http://www.finalube.com/reference_ma...Categories.htm
Pentosin is the lightest of oils, of the four above
I use their line up of oils in Porsche audi and BMW products in my garage
Its great to put something fresh in there, even better to know why it worked better, and less of a dice roll if you really know whats different about them.
I am pleased to report Second Gear Syncho shifts like butter when cold. Come drive my car if you have any doubts.
I'm also looking for data on BG syncromesh 75w85, also a gl3
seems folks have used that in ASIN trannys with much success, its cheaper. But you do get what you pay for.
sometimes, syncros dont like afluid thats too slippery, sometimes they do. I
the diy on most manual trannys and diff are the same:
locate drain and fill holes, usually a largeish hex or a 1/2 or 3/8 square drive
open fill first
then drain
reseal drain
refill till it oozes out of fill hole
seal it up
pat yerself on back
drive
drink a beer
I also considered
http://www.redlineoil.com/product.aspx?pid=140&pcid=7
its thick but not as thick as the MT-90, this one is specifically to address the cold synchro symptoms
BUT its a bit thick ish, and performs alot like the MT-90, but it MAY be an improvement
then...
surfing the net, I found this:
APPARENTLY PONTIAC USES AISIN TRANNYS
Here's some more for you... (from GM Techlink)
Quote:
Using the incorrect type of transmission fluid in Aisin manual transmissions may affect the sealing ability of the seals. An incorrect type of sealer may not be compatible with the transmission fluid or may not have the correct characteristics for sealing the affected components.
TIP: Refer to SI documentation for correct sealers, adhesives, lubricants and fill quantity for each transmission you service.
Aisin manual transmissions require the use of p/n 89021806 - Fluid, m/trns 75W-90 GL-3, 1QT (89021807, 1L, in Canada). The use of the correct fluid is required to assure the desired shift characteristics and compatibility with adhesive sealers.
RTV is the only sealer that is compatible with this fluid. The use of anaerobic sealers on Aisin manual transmissions is not recommended.
SO...
I looked up 89021806 and found its a GM GL3 fluid, seeking its KV @40 and 100 degrees
I'm trying to find its specs, but no luck yet.
What I have found tho is that the pennzoils syncromesh is NOT the same stuff as the GM syncromesh
http://www.bobistheoilguy.com/forums...Number=1421809
the history that led me to this finding is here:
http://www.ft86club.com/forums/showt...light=pentosin
If anyone local wants to drive mine, g'head. Proof is in the pudding. Now thats what my syncrho now feels like, smooth like a ball bearing, in pudding.