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Notchy 1st to 2nd shift with NSG370

TACJTJ

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Howdy. I have an 06 Sport with the NSG370 and find it particularly difficult to get smooth 1st to 2nd gear shifts. I’ve driven a dozen or so 5 speeds and haven’t encountered this issue, presumably due to not as aggressive ratio jumps from 1st to 2nd as with the 6 speed. I’ve saw that the NSG370 isn’t great and is known to be noisy and notchy, but I’m thinking smooth shifting is all me and not mechanically related.

I’ve tried shifting slow and fast, shifting at lower or higher RPM’s, and riding the clutch. Controversially, I seem to get smoother shifts or less feedback when shifting quicker rather than slower, but it still isn’t unnoticeable as 5 speeds were to me.

All other gears up and down are fine for me with no jerking. I just can’t seem to get the hang of this 1st to 2nd. Any ideas or advice? If it helps, I’m on 33’s with a Dana 44 rear.
 
More than likely it's your transmission. How many miles are on it? This is a notorious issue on the infamous NSG370.

My suggestion would be putting some Redline MTL in there and seeing if it makes a difference (it should). Otherwise your best bet when the time comes is to swap it out for a new AX-15 from @NovakConversions.
 
More than likely it's your transmission. How many miles are on it? This is a notorious issue on the infamous NSG370.

My suggestion would be putting some Redline MTL in there and seeing if it makes a difference (it should). Otherwise your best bet when the time comes is to swap it out for a new AX-15 from @NovakConversions.

119xxx on the Jeep and transmission. I did the MTL change around 1k miles ago and it definitely made the transmission more quiet. The reason I feel that this is me, is the shifter goes into gear fine. No issues there. It’s just the 1st to 2nd shift is jerky and not smooth.

Edit: I’ll absolutely be going to the AX15 in the future. I just wanna get what I can out of this one.
 
119xxx on the Jeep and transmission. I did the MTL change around 1k miles ago and it definitely made the transmission more quiet. The reason I feel that this is me, is the shifter goes into gear fine. No issues there. It’s just the 1st to 2nd shift is jerky and not smooth.

Edit: I’ll absolutely be going to the AX15 in the future. I just wanna get what I can out of this one.

It could be you, yes. The only reason I’m skeptical is because of what a known issue this is with the NSG370. Though that’s actually more of a 1st to 2nd gear crunch / grind.
 
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It could be you, yes. The only reason I’m skeptical is because of what a known issue this is with the NSG370. Though that’s actually more of a 1st to 2nd gear crunch / grind.

Right. I understand the issues with crunching or grinding into 2nd. Fortunately, I don’t have that issue yet.

I just drove it for a 30 minute “focus session” as I have several times now trying to master this thing, and I had several shifts that were much smoother when gassing while in still on the clutch a bit. I’ll continue to play and try to see if I can make it better.
 
Right. I understand the issues with crunching or grinding into 2nd. Fortunately, I don’t have that issue yet.

I just drove it for a 30 minute “focus session” as I have several times now trying to master this thing, and I had several shifts that were much smoother when gassing while in still on the clutch a bit. I’ll continue to play and try to see if I can make it better.

It’s a known issue, and there’s no R lockout, so if someone ever accidentally went into R instead of 6th at speed you will never be able to shift it better. There are a pile of weird parts inside and some are plastic which is pretty much always broke. Then one guy will come in here and say his is fine. Great. That doesn’t change that it’s a pile of Mercedes junk.
 
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This is a terrible transmission, and it's crazy jeep kept it into the JK years. I'd just look forward to when you can swap it since you did the fluid swaps many of us did. I did redline mtl and it was better until my auto swap, I've lost touch with the other party of the swap after he wrecked his rig into a ditch.
 
Im going my own direction on this one. I tried Redline and Royal purple, they both made it worse. I went with Mopar brand as recommended in service manual and found that to be the best solution for me.

I have considered the B&M shifter many times but at the cost I have not pulled the trigger yet.
 
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It’s super short. Do you ride the clutch a bit when taking off in 2nd? I tried this on flat ground a few times and the Jeep feels like it didn’t like it.

I don't like starting in 2nd, you have to use "too much clutch" - at least with 3.73s and 31s. I wish both 1st and 2nd were considerably lower.
 
Rev it up to 4k in 1st. It won’t hurt a thing and you’ll get to stay in 1st longer and make a big noise so everyone looks at you.
 
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Third to the Redline MTL... It has only gotten better with time. Between that and the B&M shifter, the Jeep has only gotten more enjoyable to drive.

I’ve already done the MTL and it for sure made the trans much quieter. My issue is the smoothness of the shift when letting off the clutch and giving gas. It’ll go in and out of gear fine.
 
It’s super short. Do you ride the clutch a bit when taking off in 2nd? I tried this on flat ground a few times and the Jeep feels like it didn’t like it.

Unless you've regeared it, starting in 2nd is not going to work with 33s on a Sport with 3.73s at best. My Rubicon has 4.10s and the stock 31s and 1st is pretty much useless on the road, so I always start off in 2nd.

Your issue is probably just due to the big jump between 1st and 2nd. It's going to feel different than changing between the other gears.
 
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I’ve already done the MTL and it for sure made the trans much quieter. My issue is the smoothness of the shift when letting off the clutch and giving gas. It’ll go in and out of gear fine.

I’m a bit lost. You should be in gear by the time you are easing of the clutch and givining it gas.
 
I use MTL as well and I add a moly containing additive. Shifts smooth. Don’t shift fast unless you have to. When I shift, I pause briefly before the next gear (unless I have to really get on it but I avoid those situations because, let’s be honest, TJs aren’t known to be race cars).
 
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I’m a bit lost. You should be in gear by the time you are easing of the clutch and givining it gas.

I am. My issue is the smoothness of the shift. It’s the jerking motion after up shifting and letting off the clutch. As I and another member said, I’m sure it’s the big jump in ratios, but I was curious if others had this “issue” and any advice. This is my fist 6 speed, and from research it isn’t a great one.
 
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