NSG370 Syncro Replacement

[LJ_Rubi]

Hey Folks,

My (new to me) 2005 LJ is at the transmission shop to diagnose a hard grind going from 1st to 2nd, a minor grind from 2nd to 3rd, and occasionally difficult to get into reverse The vehicle has 130k miles on it across a few owners so I don't know the history of it beyond the 5 years that the previous owner had it, but thus far it's my only complaint and issue I have found. The previous owner took great care of it despite not driving it much--though he was unaware of the aforementioned issues (imagine that). The transmission shop (extremely reputable in the area and recommended by several folks) put it in the rack late yesterday and are finishing up their assessment this morning but early reports are that those particular syncronizer rings are shot. I'll know definitively in the morning.

What kind of repair bill am I looking at here to have those replaced? My preliminary searches have returned everything from a little under a grand to more than double that and even suggesting putting an AX-15 in. These estimates span a decade so it's going to be difficult to predict how those remedies compare today.

Has anyone gone through this, and did you consider replacing the entire transmission? If the repair cost is around the ballpark of putting a an AX-15 (or something else, and that is for another thread) I think I'd have to consider it. I'm going to have it for the long haul and it's not my main driver, nor do I go off road...so a conservative estimate would be maybe 2k miles a year on it.

Thanks!

 

[Steel City 06]

Before replacing it, perhaps try a different fluid. It could make a difference if things aren't totally shot inside. My NSG370 grinded a lot when I used just regular Synchromesh transmission fluid. Switched to Redline MTL and they went away within a couple weeks

 

[LJ_Rubi]

Before replacing it, perhaps try a different fluid. It could make a difference if things aren't totally shot inside. My NSG370 grinded a lot when I used just regular Synchromesh transmission fluid. Switched to Redline MTL and they went away within a couple weeks

Well that is encouraging. I could always deal with it and start in 2nd gear as it has enough "umph", but I think it would irritate me after awhile. I'll see what the mechanic comes back with and see what they say about the fluid. Thanks again

 

[Camdenst]

Before replacing it, perhaps try a different fluid. It could make a difference if things aren't totally shot inside. My NSG370 grinded a lot when I used just regular Synchromesh transmission fluid. Switched to Redline MTL and they went away within a couple weeks

I had a very similar situation, 1st to 2nd was hard as well as finding reverse. Redline was a huge improvement. I also added the B&M shifter which tightened things up and helped with the popping out of 1st and reverse.

 

[LJ_Rubi]

Welp, the results are in and the syncros are definitely on their way out. I asked about the Redline fluid replacement and the mechanic said that given the condition he would feel bad charging me for that service because he doesn't think it will help. He did say that I've prob got another 6-9 months of driving on it before it's totally shot, so there is that option.
I then asked him about a new AX-15 vs re-manufactured NSG370 and he

 

[Camdenst]

https://high-impact.net/product/rebuilt-nsg-370

 

[macleanflood]

Change the fluid yourself.

Jeeps are expensive enough. If you start paying folks to do work it's astronomical...

-Mac

 

[Steel City 06]

If I were in your shoes, given it's not an immediate issue, go ahead and swap the fluid (do it yourself of course). It's fairly expensive ($90/gallon) but if it buys you a few months, that could give you enough time to make a better decision, maybe order a transmission and all the parts needed for the swap later on

 

[Duck Doctor]

Change the fluid yourself.

Jeeps are expensive enough. If you start paying folks to do work it's astronomical...

-Mac

Totally agree. Changing the transmission fluid is a simple task. No reason to pay labor.

 

[LJ_Rubi]

Not sure how my earlier response got chopped, but the mechanic is also the owner of a 2005 LJ and he said he would go with a re-manufactured NSG370 over a new AX15. Price out the door for the former is about $5k with a 3-year, 100k mile warranty on it. I agree with everyone that it's not a "must-have" at the moment and changing the fluid would likely get me a few more months than the several the mechanic said I have, but the car is new to me and as such....this is going to bug the crap out out of me every time I drive it. It makes no difference if I've got to do it now or in 9 months....and with the tax return coming in soon I might as well bite the bullet now.

 

[astjp2]

Before replacing it, perhaps try a different fluid. It could make a difference if things aren't totally shot inside. My NSG370 grinded a lot when I used just regular Synchromesh transmission fluid. Switched to Redline MTL and they went away within a couple weeks

Redline works great, majic unicorn snot with that stuff. Stupid expensive but worth it if the transmission is good. But it don’t fix this on a transmission with 3 miles on it since rebuilt.

 

[astjp2]

Not sure how my earlier response got chopped, but the mechanic is also the owner of a 2005 LJ and he said he would go with a re-manufactured NSG370 over a new AX15. Price out the door for the former is about $5k with a 3-year, 100k mile warranty on it. I agree with everyone that it's not a "must-have" at the moment and changing the fluid would likely get me a few more months than the several the mechanic said I have, but the car is new to me and as such....this is going to bug the crap out out of me every time I drive it. It makes no difference if I've got to do it now or in 9 months....and with the tax return coming in soon I might as well bite the bullet now.

Hi impact is the one I have been working with, hope it works out for you.

 

[TJ Jim]

I’ve got the nv3550 and it was a bit rough shifting with royal purple in it. Switched to redline. That made it worse. Went back to royal purple and it went back to just rough. It’s not the smoothest shifting probably even when it was brand new. Tried the B&m short shifter and that made it even worse. So these days I’m on the original oem shifter and royal purple. So maybe $100 bucks later I just deal with not the smoothest shifter but it works just dandy.
You might be expecting too much from your tranny. Gotta say you’re nuts if you don’t spend a couple of hundred bucks experimenting. $100 bucks or $2000 bucks?

Hmmmmm.