My 2nd gear synchro is starting to go. I’ve made the decision to swap an AX-15 before dumping anymore money into this transmission.
Who Has Bought a Rebuilt NSG370?
- Thread starter g.hayduke
- Start date
1. $2,200 for a High Impact replacement transmission that now has less than 5k miles that already needs a synchro
2. $630 B&M short throw shifter
3. $? All the types of oil to see if any make a difference
I tried amsoil in two 6 speeds and royal purple in one of them. I ended up going back to Mopar spec and it was the best.
I still have seen nothing that convinces me that any design flaw was fixed, or that a real, singular root cause was ever even identified (which is a requisite step before it can actually be fixed). Revised gears might have helped if the only problem was a tooth shape that didn't maintain engagement, but there are also reports of bent shifter parts and worn fork pads that may not fully engage the gears as well and the fix they released isn't going to correct those issues. It's not uncommon at all for car manufacturers to throw "revised" parts and TSB's at a problem just to kick the can down the road. The proof is in the pudding, and the pudding has 06's like mine, and later NSG's (like a wheeling buddy's 3.6 JKUR) that have the same problems with reverse.
It's a shame because the ratios really are good but as far as I'm concerned, the entire shifting mechanism is suspect and I won't trust an NSG with any Daimler parts left in that system.
When I bought mine, there were only 2 choices for breakin that preserved the warranty. The choices were Amsoil and I think Valvoline. Later they got more liberal with that. I broke mine in with whatever the non-Amsoil option was. Later, after the warranty period, I went with Redline which might have marginally improved shifting but any improvement was minimal.
Royal Purple is nothing special unless you really like purple oil. I believe the right Amsoil product should be as good as anything else but have not tried it.
When you say "Mopar spec" do you mean actual Mopar brand transmission lube or just something meeting manufacturer specs? I wouldn't use anything that doesn't meet the specs. If you do (or did), I wouldn't blame the problems you encounter on the transmission.
Does anyone know if the High Impact rebuild has the Whitbread shift rail plate?
https://whitbreadperformance.com/products/nsg370-shift-rail-guide-plate
https://whitbreadperformance.com/products/nsg370-shift-rail-guide-plate
You'd have to call and ask.
I think the problem this product purports to solve may not be a problem if you keep your hand off the shifter when you aren't shifting.
I don’t have 50k on my rebuilt yet more like 30k. I have noticed that slight pressure on the shifter while in gear creates contact between internal components that you can easily feel through the shifter. I assume some of that contact is with shift fork parts that are prone to wear. I'm betting and hoping that if I don't cause unnecessary wear on those wear-prone parts they'll last a lot longer than if I'm lazy and rest my hand on the shifter.
If it starts acting different as the miles accumulate, I'll let y'all know. So far, it's good. I never had a problem with anything but reverse. And now, reverse is 2nd nature. I don't even think about it popping out because it never does. And where before replacement, I could never be sure if it was in reverse, now, it feels like it should and there's never a question if it's in or not.
Reverse was my problem. The rebuilt 370 solved the problem at a lower cost and less work than the alternative options. It may require a little more care while driving to avoid premature wear. Or mine could turn to shit in 20k miles.
I think the problem this product purports to solve may not be a problem if you keep your hand off the shifter when you aren't shifting.
I don’t have 50k on my rebuilt yet more like 30k. I have noticed that slight pressure on the shifter while in gear creates contact between internal components that you can easily feel through the shifter. I assume some of that contact is with shift fork parts that are prone to wear. I'm betting and hoping that if I don't cause unnecessary wear on those wear-prone parts they'll last a lot longer than if I'm lazy and rest my hand on the shifter.
If it starts acting different as the miles accumulate, I'll let y'all know. So far, it's good. I never had a problem with anything but reverse. And now, reverse is 2nd nature. I don't even think about it popping out because it never does. And where before replacement, I could never be sure if it was in reverse, now, it feels like it should and there's never a question if it's in or not.
Reverse was my problem. The rebuilt 370 solved the problem at a lower cost and less work than the alternative options. It may require a little more care while driving to avoid premature wear. Or mine could turn to shit in 20k miles.
I have the reverse issue with my 2005. All forward gears shift super smoothly though. I'll have to do the rebuilt transmission eventually I'm sure and leaning toward the High Impact.
I have found that shifting the transfer case into low and then putting it into reverse works great. 99% of the time it drops right into reverse and no issues. I'm going to keep running it till other shifting issues show up. For what it's worth, I'm running Red Line MTL.
I have found that shifting the transfer case into low and then putting it into reverse works great. 99% of the time it drops right into reverse and no issues. I'm going to keep running it till other shifting issues show up. For what it's worth, I'm running Red Line MTL.
I had similar issues with R in the NSG-370. Swapped in a 42rle. Solved all my problems.
If I were you I’d start looking into AX-15 swap or if a bit more eager 42rle
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The fluid that has been in my 6 speed in the 06 for 4 years is the Mopar branded fluid sold specifically for the NSG 370. I got it at the dealer and it was not this expensive. I think.
https://www.amazon.com/Mopar-Chrysl...n-Lubricant/dp/B07VLNXLX1/?tag=wranglerorg-20
In my NSG370 I used Redline MTL and it sucked. I used Royal Purple and comparatively it was great. I never tried the Mopar.
Also, I bought the NSG370 rebuild fixture (MOPAR # 9633) if anyone is interested in it.