NSG370 transmission has anyone discovered a fix for this transmissions chronic shift problem from first geer to second geer. I have read numerous post both on the Crossfire and Jeep Wrangled. I have read that synthetic alternatives to the factory Mopar-branded conventional lubricant have been tried with little to no improvement. I also found a service bulletin (21-001-05) pertaining to 2004-2005 model year stating improper lubrication of transmission spline shaft. I have a 2006 with 46 K miles with this annoying problem of difficult shifting from first to second especially bad when cold. I have changed factory lubrication to Mopar spec lubricant with no improvement. I then changed to Royal Purple syntech that gives minimal improvement when warm but no improvement when cold. My question: has anyone found a fix to this problem? I love the car but this surely makes it less fun to drive. Thanks

 

The 1-2 crunchy shift is part of the tranny's design, particularly when cold. After much experimentation, I had great results with Amsoil.
Take a look at this thread:
Crossfire Manual Trans Fluid | ATF, Differential, Trans, Brakes, P/S | Bob Is The Oil Guy

 

Amsoil ATF or MTF?

 

It's the nature of the beast. Once you drive it more you don't notice quite as much. People here use Mobile 1 engine oil also.

 

BTW be aware that the max input torque for the 6-speed is 270 lb-ft. I suspect this is why it is not available in the SRT.

Also I supect part of the 1-2 issue is the ginormous gap between the gears, Going from a 4.46 to a 2.61 is over a 60% drop. In comparison 2-3 and 3-4 is less than a 30% drop. To really sing 1st need to be more like a 3.31. Of course unless creeping or uphill I usually start in 2nd. Will be interesting to see what change the 2.87 makes.

 

Well don't tell Josh his V-8 swap should have a trashed tranny by now.. Pretty sure the torque exceeds the value you posted.

 

Well his isn't warrented for 50,000 miles...

In general the rated max is anywhere from 50-75% of design.

And then you have Harley - since 1917 any time something broke they made it bigger. I have seen smaller gears in a Muncie.

 

I used the MTF.

 

Quick update - Changed the tranny fluid today to Amsoil 5W-30 MTL Synchromesh with very good results. 1st / 2nd gear shifts are improved, and all gear changes seem crisper. (Although I'm sure there's a little placebo effect going on).
Think that this is as good as this MB tranny will get, and will check back in if anything changes.
Again, I appreciate all of your input on this topic.

That's good enough for me!

 

Any update? Did the Amsoil do the trick or was the placebo effect going on?
Thanks

 

Only driven the car a couple times since taking it out of storage, but would say there's a marginal, not vast, improvement with the Amsoil vs. motor oil. Cold shifting (mid-50's F) is still stiff for a few minutes, but no 1st -2nd gear crunch.
I think this is as good as it's going to get with this trans. As others have stated, it shifts better at high revs.

I'll be in Dayton mid-June for a road rally, so PM/email me if you want to sched a mutually convenient time to drive my car and draw your own conclusions. Will be at Wright-Patt museum 6/15, which should be close to you.