[castrol]

I know, from what I've been able to google and search for... I've been unable to find a definitive answer. I'm hoping for some assistance.

This is my first post here as I've really had no issues with my TJ at all. It's had a transmission issue since I bought it and I knew at some point, it was going to have to be rebuilt. It's got 180,000 miles on it after all.

I've had to do some minor things here and there, but recently, the pilot bearing failed and scored the input shaft pretty heavily. Since I'd been limping it along for quite a while with bad synchros, it was time for a rebuild.

I found a shop in San Antonio that rebuilds them for a really reasonable price, far less than anywhere around Houston I could find.

Installed and ready to start rolling again with 75/90 lube in the case and holy crap is it loud. Really loud. It sounds like I've got a supercharger under the hood. Only in 1 2 and 3 though. 4 and 5 are normal and quiet just like I've become used to. I can live with the sound if necessary, but man, it just doesn't sound right.

So...all that said...Is the 75/90 the right lubricant to use in this transmission? I've seen lots of information out there. I called the manufacturer. He said 75/90. The computer information for the mechanic called for 75/90.

Something's not right so I'm reaching out.

 

[bobchase]

Your NV3550 wants a special fluid. Mopar 4874464 (it should say NSG370/NV3500 on the label) http://www.amazon.com/Genuine-4874464-Manual-Transmission-Lubricant/dp/B000TWI45M when you buy it. Or you can use Redline MTL fluid. Don't think your problem is fluid though.

 

[castrol]

Your NV3550 wants a special fluid. Mopar 4874464 (it should say NSG370/NV3500 on the label) Robot Check when you buy it. Or you can use Redline MTL fluid. Don't think your problem is fluid though.

Yeah, I'm leaning more toward the side of there being a bad bearing in there. The builder told me to drive it for 150 miles and if it doesn't quiet down, we'll do something about it.

Thanks... I researched this all day yesterday.

 

[00silverTJ]

The best fluid, from my experience with a 2000 NV3550 and reading up on the forums is going to be Royal Purple Synchromax. Pennzoil synchromesh is another option which, from my experience, is not as friendly to the NV3550. They are both made for this transmission. Redline just happens to, according to forum users, meet the specifications. I am no fan of magic ($$$) fluids and not a fanboy of anything. I just to not get why people present Redline as a single alternative when the performance of Royal purple is well documented.

Like I said I hate magic expensive fluids and avoided RP as such. My boat and snowmobile killed me with 45$ gallons of 2 stroke oil but I do it to maintain warranties. Royal Purple is just amazing in the NV35550.