musclecarman54

Sorry this is not a corvette question but it is related. I have a 57 chevy convertible that has been sitting for 3 years. Got it running over the weekend but it will not shift into drive just wants to stay in low gear going down the road. It is the cast iron trans with reverse at the bottom of the shifter.There is nothing wrong with the linkage, drained the fluid ( no burnt smell) etc. Must be internal on the Transmission. Any suggestions other than I should have been driving it a little more but would rather drive my 67 427 corvette convertible in the summer.
If this thread is in the wrong place let me know and I will remove it.

decarmine

Many, many years ago I had a '58 Chevy with the same problem. Took it to the local Chevy dealer, expecting to pay LOTS of dollars for the fix. Turns out the mechanic knew me from my route -- I was a Good Humor man and sold ice cream to his kids. I guess he took pity on me and told me it was probably the (plastic) modulator gear. It was externally accessible -- he popped off a cover, drove out a roll pin, put in a new gear, and charged me $2.00. I DID say it was a long time ago.

Maybe it's something as simple as that...

Frank

1955 copper

Did you start off in low then go to drive, if so it's the governor gear stripped not the modulator gear , easy to check pull L/S round tin cover off and pull Governor out and check gear and see if the weights move freely.

Randy G.

Is that your grand daughter sitting on the front of your car, Roy? I can't imagine you letting anyone else put their fat a$$ on it like that.

decarmine

Yes, it was a stripped plastic gear -- probably the governor. A simple fix, as you described. My $2.00 fix occurred in 1965, hence I may have mis-remembered the terminology...

musclecarman54

I had the shifter it in drive but it would never shift out of low gear. will pull the governor out tonight. Thanks.

stingrayl76

Check your vacuum line to the transmission modulator valve for a leak. If that is OK, make sure the diaphragm in the modulator valve is not ruptured.

ohiovet

Just curious about something: My 57 Corvette cast iron PG does not have a vacuum modulator valve, were they used in 57 passenger cars only?

stingrayl76

Not sure about usage on Vettes prior to 58.
http://www.ebay.com/itm/3745169-58-5...-/310893335171


According to the below reference, 55-57 Corvette PG's had no modulator:
Identifying Cast Iron Powerglides, 1950-1962

1950-54 Closed driveline, flat modulator
1955-57 Open driveline, no modulator
1958-62 Open driveline, screwed in modulator

http://www.autotran.us/identifying_1...7_corvett.html

musclecarman54

Just sit down to my computer. Read the replies. The cast Iron transmission don't have a vacuum modulator. So going to pull the governor out tonight and see if it is gummed up or broken if so it will just have to go back to the corner of the shop and wait its turn to be fixed. Have 2 other projects disassembled right now. Thanks for the responses though.

decarmine

Replacing a stripped governor was a 5-minute repair, as I recall (but it was 49 years ago!)

If you have the governor assembly in your hand and the gear is stripped just drive out the roll pin, insert new gear (I assume you can still buy the gear?) re-install roll pin, and put it back together. Not much more time involved than just putting it "back to the corner"...

You might have to drill a hole for the roll pin in the new gear -- I REALLY don't remember that much detail

musclecarman54

Over the years I have collected stuff assuming that someday I might just need that part someday. well today might be that day. I just happen to have a couple cast Iron transmissions sitting in my storage shed from 57 chevys. Checked at auto parts store for governor and all I got was a Duhhhhhhh look. You never want to throw or sell anything you have collected because someday you may need that part. It will be an easy fix if that is all that is wrong.

decarmine

Here's what I remember from 1965:

http://www.ebay.com/itm/Governor-Gear-Pin-Cast-Iron-Powerglide-Transmission-1955-1962-/231266135093?pt=Vintage_Car_Truck_Parts_Accessories&hash=item35d8892c35&vxp=mtr
That's all it took. Of course, in 1965 the $2.00 included parts AND labor...

Geralds57

I had a similar problem on our '60 Corvette. I tried several things without any luck and then I tried Lucas Transmisson Slip repair in a bottle. First time out it shifted like it supposed to and it's been that way ever since. I wouldn't have believed it could be that simple.

musclecarman54

Tried the Lucas transmission slip repair 2 days ago. You are right it could not be that easy, it didn't help. Sorry for making fun of the parts kid. I would have the same look if he told me to reboot my computer. Just a generation gap.

musclecarman54

It shifts! Talked to a gentleman who use to work at a Chevrolet dealership many years ago. He said it was not the governor because if you are driving it and let off of the gas and it pulls back down the governor is good if it free wheels then the governor is bad. He then told me to pour about a pint of brake fluid in the transmission and drive it. I was at that point I had nothing to lose. I drove it about 2 miles to warm it up still no shift up. Got in it last night to try it again and presto it shifted like it should. He told me to drive it about 30 miles then drain the fluid and put in new fluid.

ohiovet

Anyone know what the brake fluid does to help the problem?

Geralds57

I wouldn't discount the Lucas additive.. It may have helped more than you know.

5thvet

The Lucas additive is probably just brake fluid......

musclecarman54

Nope the Lucas additive was real thick like STP Oil Treatment. Thanks to everyone for the comments.