Hey everybody,

I thought i was going to be done with my 5spd swap once and for all after replacing the TOB and the ISB, but now I have symptoms of both being bad. so.....

What could cause both to have gone bad so quickly? Do I need to shim the main shaft? Did I mount the ISB incorrectly? I am at a loss to what to do. I want to save some $$ by doing it myself, but having replaced the clutch twice, TOB twice, and ISB once already, I don't like the idea of doing this more than once again....

Hope everyone is well and the Maximas are too.

 

Of course you should shim it (depending on tolerances), though I would suspect a lot of transmission shops don't bother.

Even without proper shimming, unless it is just wayyyyy out of tolerance I would still think you could get some years out of it. I can't imagine you would instantly have symptoms just from not being shimmed alone.

 

Thanks James,

That was my suspicion as well, as to why the heck would a needed shim make brand new bearings go bad so fast....

The transmission was a pain to get on there, and I may have bumped the TOB a bit whilst trying to line up the input shaft to the clutch assembly, but would that mess with the ISB? I imagine an out of alignment transmission would cause problems, meaning bad mounts perhaps.

I am at a loss to what could cause the bearings to go bad so fast..... I don't have much experience with this transmission prior to swapping it in, and it could be a long established problem within I am unaware of. It shifts smooth, though, and I don't see the pint in rebuilding the whole thing since it's just bearings giving me hell right now.

 

What exactly are your symptoms now? Are you running GL4? Sure your fluid level is correct?

 

Symptoms include:

Noise with clutch engaged and not engaged. The noise is louder without the clutch engaged, and when it is engaged it is in the 2-3000 rpm range i think.

No whining, just bearing grind in low rpm driving and evens so when the pedal is depressed during a particular rpm range.

I am running the cheap valvoline autozone has during the break in. I was saving up for some royal P or Amsoil....

I measured the amount as best I could, and it has no leaks, or so I can perceive.

Any guesses?

 

Sure bearings in trans are good?

 

The bearings surely aren't good, and they were new less than 1000 miles ago.

Hence, my dilemma, and wonder......

 

Did you clean out the case? You might have debris still floating around causing some noise, although there would need to be a lot of it or a bolt in there or something Your new bearings are most likely fine, new ones don't just fail that fast if you're NA. Finally, Valvoline doesn't make GL-4, and Autozone doesn't even sell GL-4. Don't leave that all in one stuff in there for long.

 

I cleaned the case as best as I could, but it's possible some debris got in there as I had to do some machining to remove the shaft assemblies.

I researched the fluid scenario, and I don't think Valvoline would label their product as Gl-4 safe unless they had some time and research to back it up. I know my transmission doesn't perform the same as if I had $100+ of GL-4 fluid in there, but I think that is more relative to the brass synchronizers that react to non-GL-4 fluid. The worst response I read about from the all in one bottle was some stiff shifts in cold weather. The bearings shouldn't react to the fluid, but this is just what I can gather; I know I do need to put the real stuff in for sure.

What about the TOB, would it being out of alignment be a necessary cause to crap out so fast?

 

machining to remove shaft assemblies?

GL-4 isn't the problem. I've never had a problem with bearings running ANY fluid. GL-4 makes the synchros last longer, but really doesn't affect much else.

I hate to say this, but it might be time to let a pro look at the car and how everything it together and such. saving money is one thing, but spending time and money trying to fix the wrong thing can cost you a lot more in the long run.

 

Yea I broke a punch in the pin slot on one of the forks and my only option was to grind the metal down to the point where it would be possible for me to access the pin again, without the broken punch inside of it. I may have left some shavings on the shaft assemblies themselves....

I agree, it is time for me to take it to the pros, but I am awaiting some valuable references before I take it anywhere. I want to find someone genuine and honest. I am hoping to find someone who I can pay to drive it and diagnose it with some simple answers. I can tear it apart again, I just need to know what to do..