87 5 speed???????

[leftlane]

I have a loud knock in my transmission that has just started, When I drained the trans it had ATF in it but everything I have seen shows it is supposed to have gear oil in it. Could the ATF have anything to do with what ever has went to talking in there. And does anyone think it would be worth the time and $ to try to put gear oil in it to see if it makes any difference before pulling it out. Or is it OK to run ATF in the FM145. I dont drive it but about a 1000 miles or so a year. One more thing I have a case of LUCAS 85W-140 gear oil in the garage would the be good enough for that transmission or do I need something else

 

[Taragon]

That "Clunk" is your trans bearings going out....even with the proper fluid, (and Im assuming its the 87 ranger with the 2.9) the FM145/6 you have is a POS tranny to begin with....

Pretty soon, it'll either lock up in 4th only and you wont be able to shift at all, or it'll lock up and seize in which you truck wont move with out driveshafts being removed. (Engine wont start either as the trans locks in a gear, therefore making it impossible start unless the clutch is pushed in, but even dumping it will only kill the motor and possibly break the crank or destroy the flywheel..... I've seen both happen)

 

[leftlane]

Thanks Taragon. Like I said I dont put many miles on it. It is more of just a weekend driver and bad weather truck. I guess I will just swap it out. I got lucky last year and was able to buy a roll over that still ran. Got both diffs trans and transfer case and a good motor out of it. Sold motor already.