Hot Rods This problem has me scratching my head

I decided to replace the clutch as we planned to do a lot of driving. Installed new clutch, drained the trans gear oil, (nothing on the magnet, and no gold in the drain pan).
Fully lubed and adjusted the shifter, refilled the trans with 80-90 GL5 oil.
After adjusting clutch, took her out for a spin. About 10 minutes into the ride, it began to get hard to shift in or out of gear. Pretty soon, it got to where I couldn't get it out of 3rd so I eased it home. Once home, I was able to get it into neutral.
I'm baffled as to why it suddenly does this.
Any ideas?

Specs on trans...........
Borg-Warner Super T-10 4 speed
Main body casting # 13 04 065 903 stamped above it. 4-5-78
opposite side of case... stamped WE 382
Tail shaft casting #13-04-066-903
shifter cover #13-04-097-90 D-15.78
1st... 2.64
2nd...1.75
3rd...1.33
4th...1.00
takes 2 1/4 pints of 80/90 GL5 gear oil
26 spline input------- 32 spline output

 

Sounds like clutch adjustment, like it's not releasing. Try readjusting it.

 

Sta-Lube GL-4 at NAPA.

 

Heat causes metal to expand. Sounds like the warmer your car got, the tighter it got. Adjust the clutch, drive, repeat if necessary.

 

Replaced the throw out bearing?

 

Yep... new. complete package clutch, pressure plate, throw out bearing and new pilot bushing.

 

Went to the local Napa and all they had was sta-lube GL5. tried telling me that it replaced the GL4, but, that's not what I've seen on the net. Now that I put GL5 in the trans, All the comments say stay away from GL5.

 

My local NAPA store got it out of their warehouse in town the same day.

 

Yep... that's the info I keep coming up with. Think I'll try a different Napa store.
Be draining that trans tonight.

 

Do you think my driving about 18-20 miles with that GL5 has hurt the synchro's? That would almost piss me off.

 

I doubt it hurt anything in 20 miles.

 

Does it act like the clutch is disengaging correctly? With the engine running, and the transmission in neutral, can you shift it into gear?

 

How about the pilot bearing/bushing? Lubed and free on the input shaft? If it’s too tight it can do that.

 

Many decades ago I was service manager for a dealer. I had a mechanic replace the clutch in a '66 GTO. He road tested it and had similar problems. I had him jack it up so I could take a look. He had forgotten to tighten the pressure plate bolts.

 

I bought the Sta-Lube GL-4 on Amazon. $73 for a gallon.

 

You probably could've driven for 20 miles with bacon grease in the transmission with no damage. I doubt the oil is to blame.
I agree that the clutch probably isn't disengaging.

 

Yes, goes in with no trouble.

 

I'll have to check that. It's something that never crossed my mind.

 

"About 10 minutes into the ride, it began to get hard to shift in or out of gear. Pretty soon, it got to where I couldn't get it out of 3rd so I eased it home."

Sounds like it got progressively worse during the drive, which, to me, points to the wrong lube. I have never had this particular experience, but I'd flush the transmission with kerosene (or something similar) and get the right lube in there as soon as I could. You might get lucky..

 

I just did a clutch job, on a o/t, Bought a Cheap kit on line, Looked at the pilot bushing and said... I don't know about this, It's a sintered bushing...
My case drove fine for a few week's, an started growling with foot on clutch, an down shifting... I actually did change oils also..
It'll be getting a bronze bushing soon!

 

If you're worried about the lube, drain out GL5, dump in GL4, don't make more work by flushing with anything! Not necessary, have free play in pedal? I think you need to go back and check shifter adjustment, pin in quadrant to line everything up, something left loose on linkage? If the trans slide right in flush to bell with no trouble input bush is probably fine.

 

I don't believe GL5 could create your problem in that short of a period of time.
The GL4/GL5 debate will probably go on for ever.
I suspect the clutch is not fully releasing or the pilot bushing is binding.
Will it shift into reverse from neutral without grinding, or do you have to put it in a forward gear first to shift into reverse?
If not the input shaft is still turning.
Was the new pilot bushing bronze or kinda a silver color.
The silver looking ones sold now are powered metal and have caused many problems.

Bill

 

That tells me that your pilot bushing and throw out bearing are fine. It sounds like some kind of internal transmission problem. I find it hard to believe the wrong gear lube could screw it up that quickly, if at all.

Take it for another test drive. Warm it up again, and confirm that it will still shift from neutral to reverse without grinding. Just maybe the pilot bushing starts sticking/dragging after it warms up.

 

This just happened on a customer car. They damaged the input shaft bearing in the end of the crank. When cold, it worked. After a few minutes you couldn’t shift. Pulled trans, replaced bearing, problem solved.

 

I'm in agreement with a bad pilot bushing. Did the new one pass the magnet test?

I would take another short local drive with it cold to see what happens. I highly doubt you have a fluid issue. I do use a Richmond Gear GL4 in my M20.

 

I bought SAE 75W-90 API GL-4 lube off the rainforest site...I could only get it ordered in locally, so I skipped their mark up. www.ultra1plus.com but they shipped GL-5 the first time and had to re-ship the right stuff.
It did make the transmission ( a TK-5 ) easier to shift. I had no idea of what was in the transmission for lube originally...but suspected non GL-4 due to the shelves being full of GL-5 lube
In my mind, the lube change first is the easy way to go....
Either way, good luck

 

It’s not the oil, I’ve run gl-5 in lots of transmissions that call for gl-4. I believe @squirrel has asked before for someone to actually show parts damaged from this.

 

The only issue I'm aware of with GL-5 is that some of it contains anti wear additives that can discolor "yellow" metals, such as bronze synchro rings. It won't make the transmission act like the clutch isn't working! especially in a few miles.

also, this is a T-10, not a modern transmission...they are pretty good about working if they have gear lube in them, they're not real picky. But it's also a T-10, and over 60 years old, so it could have some worn out parts that you're not aware of.

but you have to make sure the clutch is working right first. When you did the stationary, engine running engagement test, does it go into reverse without grinding?

 

No! Bones