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I currently have my transmission out of my car and figured it was a good time to address a **** issue if had with the car since i bought it years ago. When shifting to second there seems to be about a 75/25 shot that when you release the clutch that your actually in gear. the shift feels normal and positively "clicks into gear". But sometimes you go to get back on the gas and it just revs to the moon. I've realigned my shiftier and that didn't make any difference. I actually replace the shiftier with and MGW and made a zero slop linkage while that made things marginally better i still have the issue. Also, when the trans gets hot, like when its 90 out and I've been on the highway for an hour i will have the same issue with 1st, but never with any gears other than 1st and 2nd.
Any ideas? I'm planning to tear the transmission down but any input will give me an idea of what to look for. I've got this hope that is the nylon shift fork pads that are either warn, broken or missing all together. Any thoughts?
My guess is that you will find some issues with the shift fork pads. I would also carefully inspect the blocker rings and synchros on those gears for wear/damage.
While you have the drive train out, do a careful inspection of the long shift rod universal joints and inspect the shifter lower box for rear bushing wear. It most likely wont cause that issue BUT, it will contribute to poor shift quality. The universal joints are well known to have slop over time/miles. There is a forum member that sells improved lower boxes and improved shift rods. You can also do your own universal replacements if you can weld.
Thanks for confirming my gut feel Bill. I’ll let everyone on here know what I end up finding out when I tear into the trans.
Last year I replaced the entire shifter assemble, lower box included, with a MWG replacement. And I did weld in replacement zero slope u joints into that shift linkage. It did help but I still had the issue over this past year.
Bill, you don't happen to know any of the dimensions of those shift fork pads do you? I think i'm going to take a crack at machining my own. I'm sure i can get measurements of the components on the trans and reverse engineer them but a starting point would help.
Interesting is this right after the shifter install! Maybe something is off on the linkage ! You could revert back to stock if you still have it and see just as a test! Or maybe it’s your 2nd gear is spent from a engagement issue or maybe it’s all just natural worn out ! Over look your u joint install! Bent linkages ect just to be on the safe side !
These issues were present well before the linkage upgrade and since then I attempted to adjust the shifter alignment multiple times hoping i was the problem and not the transmission. I could bias the alignment to make second gear more reliable but the 1st gear issue gets worse. Since i find first more necessary i always ended up re-centering the alignment.
After measuring the existing pads and the mating components there are the drawings for the shift fork pads that i came up with. There is one mistake the internal rads need to be a 0.0625 max rather than a 0.625. Im working on machining these and will let you guys know how they turn out.
My next area of concern is the slop between the driving pin on the shift selector assembly and the shift fork linkages for 1-2 and 3-4. I was able to get some measurements which i found interesting. The pin responsible for transmitting the shifting action from the shift rod to the fork linkage measures at 0.255. However the gap in the shift fork linkage for 1-2 and 3-4 (pictured below) measures at 0.304, about 0.049 of slop. the most interesting thing is that the linkages for 5-6 and reverse, which are significantly different by nature, measure at 0.265, only 0.010 of slop which is much more reasonable. Its not that the 1-2 and 3-4 look warn or anything they seem to be simply built with more tolerance for some reason. Any idea why this extra play would be designed into these linkages and not the others. In the mean time I'll be looking into what i can do to tighten this up a bit.
Linkage with excess slop
Last edited by MAVetteGuy; Feb 8, 2020 at 12:58 PM.
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2nd Gear Shifting Issue
