Is it worth swapping in a NSG370?

bubbashubbs

bubbashubbs

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Hey guys. I currently (and unfortunately) have a 2.4 in my wrangler with a 5 speed and of course a np231. I know I have the N2550 currently, but I also got word on a 6 speed near me with low miles for a killer price. My second gear is currently a little fucky (synchro or shifter issue), so I’m considering the 6 speed as a future swap. It’s a bolt in with a different clutch and reverse switch location, but is it worth it going for the extra gear? I think it’d be better for fuel economy possibly? Anything I should look for on the trans assembly before forking the cash over? I plan on eventually running 4.56 gears. Will 1st gear be too short like it is with my NV2550 and 31’s?
 
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Are you saying the nv2550 and a NSG370 share the same engine mounting pattern?
 
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I have had two jeeps with the NSG-370s, one was at 140k and the other my current one is at 53k miles. Both shifted the same and had the same troubles going from first to second and sometimes reverse. 3-6 no issues at all ever. The reverse gear issue can be circumvented by placing the shifter in first (with clutch still down), then going to R. The NSG should have been the greatest tranny of them all but unfortunately the shifting from 1st to 2nd is horrible until you get them rebuilt, which is not cheap. I have to shift like a complete grandma from 1st to 2nd (it helps if you dont engage 1st fully, just ride the clutch a bit then go to 2nd) and can still have it grind on me or even pop out of gear. :mad: Even my dad's dump truck shifts smoother. For some reason they have no problem starting out in 2nd if the situation allows for it. The rebuild is on my list in the next couple years.
 
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I'm pretty much the only guy out there that has had multiple NSG370s, never had issues, and really likes them.

Well I say never had issues, but the synchros were shot in my '06 (2.4) when I bought it with less than 20k miles on it, I swapped another trans in I picked up for $500 and it was perfect. My '05 (4.0) has been great as well, bought with about 20k on it and have 100k now. Love the short ratios. Wouldn't have it any other way. Shifter still has a great feel to it and return to center, no vagueness, never pops out of gear, etc. Sometimes reverse doesn't line up from a stop. Let out the clutch (even just partially) in neutral then clutch back in and slide it into reverse. Takes literally a second. Certainly not the first manual trans I've had in a vehicle that behaves like that.

I think people just try to shift them like a Honda and they don't like that. It really needs to be driven like a box truck and doesn't take well to poor driving habits. Not ignoring the shortcomings, they did have issues with popping out of reverse on some of them.

That's a lot of words for me to say no, I don't recommend the NSG370 to people because almost nobody likes them.

But I like them.
 
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97' 4 Popper said:
Both shifted the same and had the same troubles going from first to second and sometimes reverse. 3-6 no issues at all ever.
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Claytone said:
needing to lightly hold it in reverse.
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And here I was, thinking it was just my gearbox. Describes my situation to a T. Somehow I still don't feel better about it... :D

97' 4 Popper said:
unfortunately the shifting from 1st to 2nd is horrible
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Try goosing the throttle between drawing the clutch and releasing or fully double clutching, it helps (most of the time). Biggest frustration with my LJ is the gearbox issues...and likely the most expensive to fix. :cautious:
 
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bluescapegoat said:
I'm pretty much the only guy out there that has had multiple NSG370s, never had issues, and really likes them.

Well I say never had issues, but the synchros were shot in my '06 (2.4) when I bought it with less than 20k miles on it, I swapped another trans in I picked up for $500 and it was perfect. My '05 (4.0) has been great as well, bought with about 20k on it and have 100k now. Love the short ratios. Wouldn't have it any other way. Shifter still has a great feel to it and return to center, no vagueness, never pops out of gear, etc. Sometimes reverse doesn't line up from a stop. Let out the clutch (even just partially) in neutral then clutch back in and slide it into reverse. Takes literally a second. Certainly not the first manual trans I've had in a vehicle that behaves like that.

I think people just try to shift them like a Honda and they don't like that. It really needs to be driven like a box truck and doesn't take well to poor driving habits. Not ignoring the shortcomings, they did have issues with popping out of reverse on some of them.

That's a lot of words for me to say no, I don't recommend the NSG370 to people because almost nobody likes them.

But I like them.
Click to expand...

So do I - I do wish it had a deeper 1st gear, but with that said, its a nice transmission. Yea, mine has the 1-2 grind - a bit of finesse and double clutching seems to help with that considerably. The so-called "difficulty" getting it into reverse is a non-issue that can be overcome by proper training - every manual transmission I've ever driven "does that" at least part of the time. I think a lot of it has to do with expectations and background. I grew up driving a truck with the legendary SM-420, and that is the standard to which I compare all others (Remind me to tell you about that truck's engine sometime ;) ). An SM-420 with a splitter would be the bee's knees, but there are multiple problems with that in a TJ. The NSG370 seems to be a good compromise, and I like the 6 speeds. If it craps out, I'll get it rebuilt.
 
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Zorba said:
So do I - I do wish it had a deeper 1st gear, but with that said, its a nice transmission. Yea, mine has the 1-2 grind - a bit of finesse and double clutching seems to help with that considerably. The so-called "difficulty" getting it into reverse is a non-issue that can be overcome by proper training - every manual transmission I've ever driven "does that" at least part of the time. I think a lot of it has to do with expectations and background. I grew up driving a truck with the legendary SM-420, and that is the standard to which I compare all others (Remind me to tell you about that truck's engine sometime ;) ). An SM-420 with a splitter would be the bee's knees, but there are multiple problems with that in a TJ. The NSG370 seems to be a good compromise, and I like the 6 speeds. If it craps out, I'll get it rebuilt.
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I didn't know any different until I joined here and witnessed the disdain....but I still don't dislike the gearbox. Big fan of 6 speed gearboxes in general, last three vehicles had them.

Truth is, I had no choice in the matter as I wanted an LJ with a manual, it was the only option. I think the biggest issue with mine was one or both of the previous owners, some folks were made for auto boxes and have no mechanical sympathy whatsoever...
 
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Love my 6 speed, operates as advertised in all gears.
That being said, at one point I put just any old oil in it, Castro from memory, and it did not like that. Became very ‘clunky, or notchy’, I’m not sure how I’d describe it.

Then read a post on here about running the right oil, red line from memory, and it’s back to being nice and smooth again.
 
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chili_pepper said:
And here I was, thinking it was just my gearbox. Describes my situation to a T. Somehow I still don't feel better about it... :D



Try goosing the throttle between drawing the clutch and releasing or fully double clutching, it helps (most of the time). Biggest frustration with my LJ is the gearbox issues...and likely the most expensive to fix. :cautious:
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I haven't tried hitting the throttle between shifting. I have put the shifter into neutral and then second without actually letting the clutch out in neutral and it seemed to help. I just drove my LJ for the first time in a couple months and ended up in some stop and go traffic. It wasn't too bad although there was a slight grind in 2nd at one point. Still the shift from first to second is so janky and awkward I had a truck swerve around me and cut me off because I built up too much speed in first (like a couple mph too high) and had to slow back down a bit to shift into second. He saved a grand total of zero seconds on the clock but honestly I get why he did it. It's better just to keep the thing rolling and forget about first if possible.
 
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97' 4 Popper said:
I haven't tried hitting the throttle between shifting. I have put the shifter into neutral and then second without actually letting the clutch out in neutral and it seemed to help. I just drove my LJ for the first time in a couple months and ended up in some stop and go traffic. It wasn't too bad although there was a slight grind in 2nd at one point. Still the shift from first to second is so janky and awkward I had a truck swerve around me and cut me off because I built up too much speed in first (like a couple mph too high) and had to slow back down a bit to shift into second. He saved a grand total of zero seconds on the clock but honestly I get why he did it. It's better just to keep the thing rolling and forget about first if possible.
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I tend to do a throttle blip on downshifts while double clutching - just basic driving instinct on my part, but it seems to particularly help with this transmission (and the SM-420 for that matter). But your post underscores the one thing I don't like about this transmission. First gear is too low for the road, but not low enough off road. The so-called "Wide Ratio" version that I've only read about on Novak's site, sounds like it would be a better match. 1st and 2nd are both lower, so 1st would be nicer off road, and you just might be able to start out in 2nd the way the Gods intended. Yea, you can start in 2nd with the "normal" version as well, but it uses a bit more clutch than I like.
 
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