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4+3 blues


Jan 17, 2008
1986 4+3 pace car
;help I noticed guys after snatching 2nd at about 5500rpm a little grind going into 2nd gear .. at the next light it seemed that shifting into 2nd gear the shofter seemed to have to travel further down n2 the 2nd gear gate than ususal.. days later i happened to shift to 2nd and got n2 the throttle and abruptly got off the gas as the car began to coast down the shifter bumped making a clunk sound i did it again and it did the same thing except this time it jumped out of 2nd n2 neutal...i figured possibly i messed up a syncro... this is a car that i at best drive 2-3 months out of a year....well about 4 moths late i took it out everything seemed finewhile riding in 4the gear i came to a stop sign.. took the shifter from 4th to neutal then to 2ndand the shifter was as if the shift rod had came loose..when i tried to go to 1st the it felt the same .. the only gears that worked were reverse and 3-4.. i looked under the car and the shift rod was still sonnected to the 1-2 lever on the trans i could push the 1-2 lever back and forth on the trans as if it was conncted to nothing ..
a guy told me at a manual trans rebuilding shop that the problem could be a broken 1-2 shift fork or excessively worn..he says that it can have so much wear that it doesnt engage 2nd all the way and it could cause it to bump the shifter and jump out as well as possibly doesnt have to be a syncro.. im wondering do i have to remove the trans or can i take the side cover off the trans with it still up in the car to see if the fork is broken or worn.... also .. 2nd issue:: does anyone know where i can purchase the back up lite switc as well as the shift switches four 2nd 3rd and 4th .. the od unit works but whenit wants to .. i could shift to 2nd and somtime it comes on but most tims not..if i push the button it does nothing .. at times it will engage by itself when i shift to 3rd gear.. and even then when the od comes on i can push the button but it willnot disengage i have no clue ..all replies greatly appreciated ..:confused
Like someone mentioned to you, the forks bent can throw in the gear so much. The fork is bent back from the gear popping out. The drum with the switch is just hanging in dare with the notch slightly not there since the forks are bent and the linkage might be fine externally, but the bend or burnded down fork to slide and stick the gear in place is bending back on it's heels and when that gear loads, it wants to pull out and with that much slop, the fork face is burned off bent and ****oshift is the result.
two different problems

My first thoughts were that you sound like an aggressive shifter, which is fine, but can be harder on the components. Then I thought the bushings in the linkage were well worn or missing, relatively easily checked and replaced with the tranny in the car.

Your tranny guy might be right, but get a second, qualified opinion. One piece of info missing is the mileage on the car. At 105k (I am not a real aggressive driver but I do DRIVE) we found that the case hardening was gone from 2nd gear and all gears had micro cracks; due to fail at any time. For yours, it might be time for a rebuild.

The O/D is a bit complicated but a very good unit, IF properly maintained and the driver understands it. There are many posts on that Nash unit and the symptoms you describe could be caused by a low fluid level, a failed internal component, a bad switch or need for an engine tuneup.

Check for proper fluid level and color/smell of that ATF. It, and the filter should be changed periodically, perhaps as often as 10k.

I know it sounds 'out-there' but I fixed my O/D cycling issues by changing spark plug wires. honestly, that was all I did and the unit worked perfectly afterwards. The ECM needs to be in closed loop (warmed up), of which the O2 sensor input must figure in. The old wires, I reasoned, were causing an incomplete burn, telling the ECM that the car was still cold with the rich exhaust. The car was also running rich due to some mods and a mediocre chip re-do.

Thirdly, if those are okay, mess with the switch and see if it is problematic, as some here have found.

There is a great rebuild firm in NY, if you should have to get inside the unit.:w
thanks guys ! the od unit is good nothing wrong with it mechanically it shifts and down shifts firm like it should only before started having problems with the 4speed; the od unit wouldnt take command fromthe pushbutton on the shifter and alot of times it wound engage when the coolant temp reached over 120 or so like it nortmally would ..it sometimes would engage when i shifted to 3rd gear but even then when i hit the button to disengage it it wouldnt shut off only if i pressed down the throttle it would kik back into 3rd direct and sometimes it wouldreturn 2 od in 4th but othertime it would not come back on in 4th gear.. the only thing i canremember is that i did disconect the back up light switch because it broken..i wonder if that has something to do with my problem.. i do want to repace all of the switches for the od.. but dont know wher to find them or what they cost and i cant seemto find the back up light switch anywhere..
If you're still having problems with the O/D acting erratically, check the relay on the firewall. It's on the LH side just behind the fuel pump relay. I was having a lot of problems, and found that the wires were bare leading into the connector. The circuit 901 was getting occasional current from another 12V wire, causing the O/D valve to think it was supposed to shift.

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