MN12 Grinding third gear?
#1
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I took the car to the track yesterday. I was spinning pretty bad through first and second. I short shifted to third cleanly and then fourth. When I got back on the return road I noticed that the car didn't want to shift into third with out a horrible grind. None of the other gears grind and the grinding goes away once the car is stopped. It did this the whole way home. So I just went from 2nd to 4th. Did I ruin a syncro or something? I would geuss the 3/4 shift fork but it doesn't grind 4th and shifts fine at idle. It has been hard to get into reverse since I got home from Iraq. What do you guys think is wrong?
Brett
Brett
#2
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Originally Posted by Pray
I took the car to the track yesterday. I was spinning pretty bad through first and second. I short shifted to third cleanly and then fourth. When I got back on the return road I noticed that the car didn't want to shift into third with out a horrible grind. None of the other gears grind and the grinding goes away once the car is stopped. It did this the whole way home. So I just went from 2nd to 4th. Did I ruin a syncro or something? I would geuss the 3/4 shift fork but it doesn't grind 4th and shifts fine at idle. It has been hard to get into reverse since I got home from Iraq. What do you guys think is wrong?
Brett
Brett
If it is in fact a bent shift fork, I'd invest in an aftermarket shifter, something like a Pro 5.0 with stop bolts. That will ensure you don't ever bend another shift fork
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Could be the blocker rings. I had mine go out on my transmission because they do not have the best friction material on them. Either way when it is apart make upgrades like the shift fork.
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its a blocker ring... REPLACE IT AND GET IT FIXED NOW lol..
i just had mine replaced... i drove it with it grinding but just RPM matched and didnt force stuff..
i ended up with a 1500 dollar rebuild rather than a 700 dollar rebuild ... t56 rebuilds.com just got done with mine. it drives and shifts AMAZING !
i just had mine replaced... i drove it with it grinding but just RPM matched and didnt force stuff..
i ended up with a 1500 dollar rebuild rather than a 700 dollar rebuild ... t56 rebuilds.com just got done with mine. it drives and shifts AMAZING !
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Shifting with the wheels spinning is a real bad idea. It will burn the friction material up ( what I suspect you did). You will need a teardown and I suggest a fork upgrade. It still will not survive spinning shifts long.
#7
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So you guys think I am looking at a blocker ring. I tried calling T56rebuilds today but I didn't make it before they closed. I am going to talk to them tomorrow and see what they think. I will order the parts then and do the rebuild if there are no special machines needed. I am also going to change the shift forks while I am in there. They seem like cheap insurance. I have rebuilt three or four autos with pretty good success. I also used to run a machine shop where we had to do large gear boxes so I should be alright. I just can't afford a whole new tranny right now. I will definately up grade later considering I am putting out well over 600rwhp with out the restrictor plate. I have been avoiding third like the plague. I just run 2nd up to 3,500 and shift into fourth. It is working so far. But not the best solution. Thanks for the input guys.
Brett
Brett