OK - I know this is a cross-post, but I'm hoping I can get more useful input from this forum than the General Discussions one....

"Well, my wife just drove from central Massachusetts to southeast Connecticut, about a 2 hour drive. She called me when she got to her destination and said very ominously "the Jeep isn't shifting right". Every time she shifts into second gear, the gears grind hard. All other gears (including reverse) are "crunch" free. Additionally, I had her go out and just idle the KJ in neutral, and then step down on the clutch and shift into all the gears, one at a time. Only second crunched, and it was loud enough for me to hear it over the cell phone. I'm having her just skip second gear and come back home to bring it to the dealer.

This is an '04 KJ, with 3.7/NP231/5speed combo, and it only has 23,000 easy miles on it. I realize that the NV3500 isn't considered a heavy-duty transmission, but cripes, this ain't a CRV, either!

Anyone else have synchro failures with their manual tranny KJ's?? I have to say that I'm EXTREMELY dissapointed in this failure. We bought this KJ based on the bulletproof reliability of my own XJ, but that is obviously not the case....
"

I've been around here for a few years...can't remember hearing this problem before.

Good luck ...keep us posted

Well, she's not coming home till Saturday, so the earliest I'll hear anything from the dealer is Monday.

I suppose it's good that it's not a common problem, although it doesn't really help me directly....

Tell me this - is it a reasonable expectation that I'll get a new transmission out of this? Or will the dealer try to pull the tranny apart and do minimal repair work by replacing the synchro rings (and anything else broken)?

I don't really want a rebuilt transmission in a vehicle with only 23K on it....

if just synchro's in 2nd are bad, they'll just replace them. My front diff went with 30k and they rebuilt it. Tech said it was set way out of spec from factory. I guess if it's rebuilt right, it's better than factory. In theory!

Keep up posted (and keep your receipts!)

_________________
Adam
KJ is SOLD for a JK Rubi Unlimited!
2003 Renegade.

http://www.cardomain.com/ride/3199258

JeepTales

I'd ask them to replace the transmission since the KJ is pretty new. The worst they can say is no...and then fix the syncro.

You cant get more than you ask for ...thats for sure

I was assuming they'd try to skimp and just replace the synchros. My beef with that is 1) they're going to split a perfectly good case to get to the guts, and I just don't have much faith that it'll go back together leak/trouble free, and 2) if synchros can go bad in 23K, then who knows what else is bad in there, and whether the tech will catch it. I don't want to do this again.

But! Who is to say a new tranny won't develop the same or another problem.

_________________
"CHROME DON'T GET YOU HOME" "Just because I don't care dosen't mean I don't understand" Homer J. Simpson

Webshots

I'm *assuming* that nothing will go wrong again for two reasons:

1) The NV3500 is a fairly strong transmission, and despite the KJ being rather heavy, it's not throwing a lot of power through the tranny.

2) Because of the lack of info on failures of this type, I have to assume that this is a freak problem, and that there isn't an inherent flaw in it's design. Hopefully it was just a synchro with a casting flaw in it, or the tranny was a "Monday morning" transmission, and a shim/spacer/c-clip or similar was installed incorrectly.

Anyways, synchro failure is usually due to either an individual component failure, or to a poor overall design. "Hard use" of a vehicle (i.ie. towing or wheeling) has virtually no effect on the life of synchronizers. All they're doing is just matching speeds of adjacent gears.

That being said, or KJ has nver been used to tow, has never seen more off-roading than a grassy field, and has never even been over 4000-4200 rpms. This is not a hard use vehicle, so I'm hoping this is just a random component failure.

Sorry I never reported the outcome of this issue....my initial suspicion was correct - 2nd gear synchro was garbage. The dealer ended up replacing 2nd and 3rd gears (they were chipped), plus the 2nd gear synchro. I looked at the parts when the tranny was split, and the tabs on the synchro that fit into the corresponding slot on the face of the gear were completely sheared off.

Also, just going from my experience tearing down other transmissions in the past, the 4 tabs on the synchros looked very light duty. Oh well...