Hard shift into direct drive

toyota
supra

#1

1983 Celica-Supra P-Type, 38K miles. Garage kept, never abused… I have a really hard time shifting into 4th gear. Rebuilt clutch master & slave, adjusted pedal. Buttery smooth 1st-3rd. 4th does not grind but requires a lot of force to shift. 5th shifts ok, but feels vague; hard to tell it’s in gear.


#2

Have you checked transmission oil level?


#3

Synchros . . . ?


#4

Yes. Clean and full AMSOIL 75w90 GL5. Changed anyway.


#5

With a car this age the linkage can get worn and out of adjustment. That’s what I’d check next.


#6

Doubtful. Does. Not grind one bit.


#7

Maybe something is under the boot by the shifter, or clogged up by debris etc. PS a friend had one of a similar vintage we did some touring in, great car!


#8

GL5 may be damaging your transmission. Although your immediate problem is likely a synchronizer or the intermediate bearing problem unrelated to the oil GL5 is a rear/drive axle lubricant and is a blend that deteriorates synchronizers. Is there a whining noise when idling in neutral with the clutch released?


#9

Solved. Shifter knuckle bushing cracked.


#10

Good that its solved but I think you should check to make sure the fluid is approved by Toyota. I don’t know much about GL5 vs GL4 except when trying to get the right stuff for my snow blower, but I do recall an issue with the one not being compatible with some bearings. So I’d get the stuff from the dealer to make sure you’ve got the right stuff.


#11

Have the original owner’s manual which specifies GL5. Also spent 10 years in the service department of a Toyota dealer. We use this fluid in all of our cars without issue. Thanks for your response.


#12

Well that answers that issue.


#13

Not all cars use GL5 in their trannys. Toyota’s older W50 5 speeds specify GL4.
If you search for the phrase GL4 vs. GL5, you’ll find that GL5 is reported to damage brass synchros.


#14

Just curious, where is that part located? Under the shift lever? Or on the side of the transmission? Or where?