NV3550 is now making noise

[jasonv]

Hi,

So my nv3550 Started making noise any time I shift gears. I get a mild grinding noise just before I go into gear, any gear.

The bad part is that it was fine for the first 1000 miles around town. I took it on its longest rip yesterday, 30 miles at freeway speeds 55-60 and then had Pone incident of a much higher pitched squeeling when I shifted gears. Almost like a bad bearing sound.

I am running the amsoil fluid for it. There seem to be plenty of noisy 3550 threads on the jeep boards.

Any suggestions?

Thanks,
Jason

 

[blubuckaroo]

Could it be the throwout bearing making the noise?
I hate to hear this stuff. I just finished putting in the NV3550 kit. Why did you decide to use Amsoil instead of the Mopar oil?

 

[73stallion]

did you oil or grease the pilot bushing before you installed it? could be the problem. is in mine.

 

[blubuckaroo]

did you oil or grease the pilot bushing before you installed it? could be the problem. is in mine.

You know, that is strange they don't want you to grease it. I remember using lubriplate white grease on all the pilot bushings back in the day. When I called Advance Adapters, and the guy actually warned me twice about that in the same phone call.

 

[barronj]

I don't know about the NV3550, but I've known plenty of T-5's (mustang transmission) that would grind when going in to gear if the clutch was not properly adjusted. If you're not able to shift until the bottom of the pedal, then that would be a symptom.

 

[jasonv]

i don't think it the pilot bushing, I have a bushing, I think they had me soak it in oil before I put it in? no noise or bad feeling when I step on the clutch alone.

clutch in, truck rolling with gravity I get noise/feeling when shifting.

The noice comes only when the transmission is spinning and it's right when you start to get resistance putting it in gear. Although it's starting to sound like maybe it's in the rear half of the transmission nd I get a larger noise when I start moving then it goes away.

I went Amsoil because it's approved, some people liked it better, and it's $50/quart cheaper than the Mopar stuff.

Jason

 

[73stallion]

i ran amsoil in mine for a while, didn't like the way it sounded. went with the mopar stuff AND added some lucas oil stabilizer, i like it a lot better.

 

[Izzy]

i ran amsoil in mine for a while, didn't like the way it sounded. went with the mopar stuff AND added some lucas oil stabilizer, i like it a lot better.

X2, Mine was very noisey when I first put it in but I did the same as stallion since he recommended it and it helped a bunch. I also added a touch more oil then it called for as recommended by Advance adpaters and that helped as well. You can't really put too much.

By design, the NV3550 4th and 5th gears are high in the housing so the extra oil helps keep them lubbed up.

 

[jasonv]

Sorry I read throwout and thought pilot because that's harder to fix, always thinking the worst, but I think the noise holds true, not by clutch movement by transmission movement

I can shift before I get all the way to the floor.

I need to pull my access cover and see if it sounds more clear.

Jason

 

[MarsChariot]

Yes, I would recommend the Mopar NV3550 gear oil. It's made for it, and I have not heard good results with the substitutes.

 

[blubuckaroo]

I bought the kit from Toms and they sent two qts of the Mopar oil. Trouble is the transmission holds 2.2 qts. When I bought the third qt, I thought I had misunderstood when the guy at Chrysler asked for $20.?:?
I've had a loose fan belt squeal whenever I shifted. Sounded like it was coming from under the car.

 

[VT_Don]

I've rebuilt a few NV3550s now, add noted most have suffered from lubrication related wear. The fill plug is very low on the case and any fluid loss creates a critical condition. The design is such, that at a modest approach angle, all fluid goes to the rear of the case, and the oil slinger on the input shaft can be ineffective.

I plan to fill my 3550 a couple inches above the fill plug thru the shifter opening. Regarding other comments, there is NO inspection cover on a 3550, and the pilot bearing should be Oilite bronze. Greasing Oilite may destroy its function. In my experience, most shifting issues/grinding are due to clutch adjustment. Keep in mind, this is a light truck transmission and not intended for speed shifting. Treat it gentle and it will last a lifetime.

 

[blubuckaroo]

I've rebuilt a few NV3550s now, add noted most have suffered from lubrication related wear. The fill plug is very low on the case and any fluid loss creates a critical condition. The design is such, that at a modest approach angle, all fluid goes to the rear of the case, and the oil slinger on the input shaft can be ineffective.

I plan to fill my 3550 a couple inches above the fill plug thru the shifter opening. Regarding other comments, there is NO inspection cover on a 3550, and the pilot bearing should be Oilite bronze. Greasing Oilite may destroy its function. In my experience, most shifting issues/grinding are due to clutch adjustment. Keep in mind, this is a light truck transmission and not intended for speed shifting. Treat it gentle and it will last a lifetime.

So how much oil in ounces would you recomend over the normal fill?

 

[VT_Don]

re: "So how much oil in ounces would you recomend over the normal fill?"

I would estimate 1-2 additional quarts. PLEASE understand this is just my unproven idea. I have yet to test this and there may be an adverse effect. On many transmissions, an overfill will puke oil out the vent tube resulting in a possible fire if contacting a hot exhaust.

 

[Izzy]

Th tranny shop I bought my NV from suggessted I put an extra quart in mine. Said it won't hurt a thing and if it has too much, it will seep out the breather vent and that's not, not a bad thing.

Advanced adapters essentially said the same thing so I did it, haven't worried about it and haven't had any noises since.

 

[blubuckaroo]

I like it when more is better!
It just gets me in trouble when torqing bolts and adding fluids.%)
Put the rear up on blocks and have someone run it through the gears while you listen.

 

[IFLYHOOKS]

Noise

I had what sounds to have been a similar noise to yours. Originally thought it was the throwout bearing, but come to find out the housing around the input shaft had broken off. i took it to a local welding shop and had it welded back on, works like a champ.

http://classicbroncos.com/forums/showthread.php?t=168771

 

[jasonv]

I was just about to post that Blubuckaroo hit the jackpot, I was totally convinced it was the throwout bearing and my mechanic agreed. The noise is much more constant now. Only happens with the clutch in and stops when I let it out.

I had added an extra quart of fluid and that seems to improved the shifting unless it was the repositioning of the shift lever.

I guess I will know as soon as I pull the transmission in the next few days.

Jason

 

[blubuckaroo]

I understand these NV3550s are a little noisy if you don't have carpet padding. I really do think though most of the issues haven't been the transmissions fault but improper installation items like improper oil, pilots, throwouts, and alignment. My son has one in a Jeep TJ with over 100K miles and it has never even had the oil changed. I've got less than 50 miles on mine now, so we'll see...

 

[jasonv]

Yes I understand d they are noisy and can see that after 1000 miles. But this is totally different. Nothing should make this noise. I really suspect it's a bearing in the transmission input shaft and am going to try to talk to a local shop to see what replacement involves but otherwise I am going to go the $50 and swap the throw out bearing.

I still have to check the measurements so there is that also.

Jason