NV3550 Synchromesh Fluid Additive

[MarkAllan]

2002 NV3550 - I've got some synchromesh issues going into second from first. I would like to prolong a rebuild or replacement a few more months. I'm currently running the mopar factory recommended fluid, which I just changed, but I'm wondering if there is an additive I can use to help with shifting a bit smoother. Any suggestions would be appreciated. Thanks!

 

[Mobusaki]

I can't answer the additives question, but I have the same issue, since I got the Jeep ~10 yrs ago. Tried a bunch of different fluids back then. Settled on the last thing I tried, Royal Purple. Seems a bit better than the rest but the issue is still there. What helps me is to move the shifter toward 2nd, but not all the way... just pause a moment before shifting into 2nd. I can feel when it is ready to go in, it's like something "catches" and then it shifts smoothly. Very difficult to describe, I'm sorry. Experiment and if it's the same as my Jeep you'll see what I mean. The other thing that helps is double clutching/rev matching, of course, but I don't always feel like doing that.

 

[MarkAllan]

Thanks Mobusaki, I know exactly what you mean about "..not all the way.." I do exactly the same thing now. And also like you I don't always feel like double clutching or rev matching. I was thinking that maybe an oil thickener would help being as the transmission is just made up of gears and bearings with no valve bodies or pumps.

 

[TheBoogieman]

I used RP in one of my old Jeeps with the same issue. Made it slightly better, and it never got any worse.

 

[rweathers2001]

I am running Redline MTL in mine and have found it to work the best. The shift from 1st to 2nd is not perfect but much better with Redline. I have tried RP, Amsoil, and regular Synchromesh in it over the years and Redline has worked the best.

 

[C.J. Roberts]

I run the Redline MTL also. I was having SERIOUS shifting problems, but it fixed most of them, until my 3rd gear syncro crapped out. As long as I take my time going from 2nd to 3rd, it shifts alright. But if I were changing the fluid, I'd stick with the Redline.

 

[MarkAllan]

Thanks everyone...I love this forum given how helpful everyone is!! I'm going to start with trying Redline MT-90 75W90 GL-4

 

[C.J. Roberts]

Thanks everyone...I love this forum given how helpful everyone is!! I'm going to start with trying Redline MT-90 75W90 GL-4

NO! NO! NO! Redline MTL is what you want. Red Line MTL 75W80 GL-4

https://www.amazon.com/Red-Line-Transmission-Transaxle-Lubricant/dp/B00NTEWQ1U/?tag=wranglerorg-20

 

[MarkAllan]

NO! NO! NO! Redline MTL is what you want. Red Line MTL 75W80 GL-4

https://www.amazon.com/Red-Line-Transmission-Transaxle-Lubricant/dp/B00NTEWQ1U/?tag=wranglerorg-20

Got it...I was wondering why some were referencing MTL and not MT, but I get it now....thanks!!!!