4 gear grinds but can go into gear with a bit of force

[ziggo0]

Well, I got a used transmission off a member here. 74k miles on the transmission, looks very very clean, he said it had no grinds or any issues with the gears. I got it in and it felt very nice, much more solid than my old dead transmission - EXCEPT the first time I went to go into 4th...put it in 4th, slowly released clutch and it grinded/kicked me out. Tried it again but held it back in 4th and slowly released the clutch and it stayed in gear. So far it really only goes in if I hold it in gear pretty hard and slowly release the clutch. My linkage is good, did skateboard bearings for shift bushings at the transmission. The bracket is solid and the cables aren't binding.

I pulled off the cover on the side of it and the nuts were loose, fixed that up but didn't help 4th gear. I noticed when the cover was off if I put it in 4th and rotated the gear myself it felt like it was skipping but it still wanted to turn the axles. I grabbed the weight where the shift linkage connects and pulled it back into 4th as far as it would go and rotated at the same time - it was fine - kinda had to 'slam' it into gear if that makes sense.

My conclusion is shift fork/selector or something with the rail perhaps? My dead trans just had a differential issue...it shifted perfectly fine. Would it be possible to swap the 3/4th fork (if damaged) and/or rails if need be? I'm on a sever budget after having to pull the money for a transmission out of nowhere...other than that this tranny is great. Thanks for the advice.

 

[ziggo0]

Despite the outrageous amount of enthusiasm from the community, I'd just like to update this thread with my findings.

I tore apart my dead transmission to get the hang of it - and to be honest, it really is quite simple to dissemble our transmissions. I found that a gear in my diff was missing a tooth, it seemed to cause damage on the way out, made 2 holes and that was done. For 150k miles - the gear set looks to be in superb condition...so I'm going to hang onto that. The forks for 1/2 3/4 5/R had very VERY little play in it - pretty much none.

With the confidence gained I pulled my transmission this morning and got it apart. This transmission was in much better shape. To recap I could pull it into 4th and get it into gear but only with excessive force. Basically it would grind if I put it into 4th and eased the clutch out. My findings were the 3/4 fork was severely worn. 3rd gear side seemed to be just fine...had no issues with that - but 4th gear side was worn so far away that I'm shocked it even worked.

So I transplanted the good fork from my dead trans, cleaned up the magnets, checked the diff etc, got it all back together and 4th works like a charm! I'm stoked! I'd like to thank Tim Zimmer for this guide I found while searching: http://www.dsmtuners.com/forums/drivetrain-tech/390941-broken-3-4-shift-fork.html#post152454232

 

[TSi Kid]

I don't think anyone commented on this thread because it was kind of a "duh" reasoning for your problem. Glad you figured it out though.

 

[ziggo0]

I guess I didn't see it as a 'duh'...was just looking for confirmation in my assumption I guess. Glad I went through with it either way. The learning experience is invaluable.

 

[TSi Kid]

You got no response because it was posted in the drivetrain tech, As bad as this sounds, you posted in the correct spot but because it wasn't in the newbie forum, nobody looked at it.