amsoil FGR vs MTG in a tranny

Messages
193
Location
MN
The only amsoil in my area was availibe at napa. My nissan 240sx requires a weight of 75w90 gl4. This was durring a trans swap so I had to get something to get on the road. The amsoil that was availible was the FGR longlife synthetic gear lube 75w90. I thought I was good to go. Its been about a week with the fluid in the tranny, however I stumbled apon some info that worries me. It seems the FGR is ONLY for diffs, not transmissions, and for the transmission the MTG aka the synthetic manual transaxle and gear lube. Will running the FGR in my transmission that has brass syncros damage the transmission? yes the FGR IS GL5, but I dont know if amsoils diff fluid would work in the tranny. Thank you! PS I plan to order the MTG, however I just need to know if the FGR will work for a couple weeks.
 
Messages
2,689
Location
South Carolina
It won't trash your tranny in a couple of weeks, unless you are just grinding the gears mercilessly currently for some reason. Just change it out when the MTG comes. MTG is much better suited to the frictional needs of your synchronizers and the viscosity of MTG probably a slightly better match as well. As they say Down Under, No worries, Mate!
 

Bigsyke

Thread starter
Messages
193
Location
MN
cool, yes im in the process of breaking in my clutch, so im going very very easy on it.
 
Last edited:
Messages
8,756
Location
RI
If the tranny is shifting fine, you can use it as long as you want. Get your money's worth. I'd use it for 30k or 2 years whichever comes 1st. Nissan makes a great MTF 75w85 too.
 
Messages
19,479
Location
Chicago Area
I would have waited for or ordered the correct fluid. You only do this every 2 years or so. I am pretty sure the Amsoil is not eating away your synchros - it is buffered or neutral. But shifting is certainly compromised. If you have no problems shifting with your driving, you can leave it in. Cold weather may reveal some nasty tendencies.
 

Bigsyke

Thread starter
Messages
193
Location
MN
Shifting has been a little notchy, however im not taking the rpms over 2.5k due to a lightweight flywheel. Usually the shifting gets a little better after the trans warms up. I may drain the fresh fluid and put it in the diff since it was about 40 bucks for 3qts. overall it still is pretty good considering the tranny had some worn gears and was reported to have a nasty 3rd gear grind. Hopefully I can find some MTG and give that a shot without ruining my trans in the meantime. Thanks for the replys!!!
 
Messages
39,806
Location
Pottstown, PA
Use AMSOIL Extended Drain Synthetic Gear oils in differentials, manual transmissions or other gear applications where one or more of the following standards are specified: API GL-5 & MT-1, No worries about the soft stuff.
 
Top