420A 5th gear

[camsmurdered2g]

Fresh gear change with atf4, no metal shavings at all. Pops out of fifth when under pressure, like going up a hill or decent acceleration. I noticed that it feels like the gear isn't fully engaging. Shifts into the gear fine, doesn't grind, but when it is the the gear you can move the gear shifter another 1/4 inch or so. No other gear does this. Bushing? Linkage? Let me know your input. Reverse seems perfectly fine also.

 

[GIRman67]

It sounds like you're using a M/T why are you putting Automatic transmission fluid in it? shouldn't you actually be using gear oil like 75/90 or close?

 

[bullettdsm]

It sounds like you're using a M/T why are you putting Automatic transmission fluid in it? shouldn't you actually be using gear oil like 75/90 or close?

Because he has a 420a with a nvt-350. You shouldn't put gear oil like 75/90 in it as that can wear the fibride synchros early. What is currently recommended by Mitsubishi and Chrysler is the ATF-4.

As for the 5th gear pop out; yeah, you started with the gear oil, good. Next would be to inspect shifter cables, mounts, and bushings (also motor mounts just to be sure). They are all a possibility. As you are suspecting, MAYBE there is some wear that is keeping you from going all the way in. Why are you checking these things? Because you want to stay away from the most likely culprit; wear in the trans normally caused by oil problems over the years (not servicing. getting too hot, low oil, blocked oil passages etc.).

So check the cheap/easy stuff first.

 

[jayson427]

Because he has a 420a with a nvt-350. You shouldn't put gear oil like 75/90 in it as that can wear the fibride synchros early. What is currently recommended by Mitsubishi and Chrysler is the ATF-4.

Really? wow I have always put gear oil in my tranny, it's been about 3 years, I wonder how bad that is? I always change the oil every year too. When I got my first 420a I'm pretty sure it had gear oil in it when I drained it so I put that back in.

As for the 5th gear I would think it had to be in the shifter and bracket. Must not be holding it in place. Take your center console out and check it out. There's a spring on the end of a bolt that might be worn out on the shifter bracket.

 

[bullettdsm]

Really? wow I have always put gear oil in my tranny, it's been about 3 years, I wonder how bad that is? I always change the oil every year too. When I got my first 420a I'm pretty sure it had gear oil in it when I drained it so I put that back in.

Yeah, early on New Venture had a specific oil out that was made by Texaco. it was pricey (up to $25 a quart) but I loved it. It had whatever modifiers in it that were necessary for the fibride synchros not to break down. A few years back, in what proved to be a cost savings measure, they started recommending the ATF-4. Hands down the original "special" fluid gave me much better shifts.

But I digress. Most of the current gear oils out there don't have this specific modifier. BUT I do know that some people have not had a problem yet with synchromesh (I believe Paul, Velocita, is one of them) but it is not recommended. As for me, I use Amsoil high mileage synthetic. It has the necessary modifiers.

MB

 

[VelocitàPaola]

I've had SynchroMesh in my MTX for about eight years now, but admittedly, I haven't driven it much in the past two to three years.