Question about 1981. 4-speed shifter
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Race Director
Joined: Dec 2003
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From: Fremont Ca
2022 C4 of the Year Finalist - Modified
Question about 1981. 4-speed shifter
Cars got 4600 miles and has sat since 2007 more or less. The shifter is very tight,not smooth at all. What would cause this to be so stiff,clutch is smooth no issues there.
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Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
All gummed up. All the grease is dried out. 45 year old car , never used. That's horrible for any type of machinery. I'm certain you will finds lots of things to clean and regrease and lots of rubber parts that have perished.
Race Director
Joined: Nov 2006
Posts: 13,248
Likes: 7,839
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
I tryed a synthetic gear oil in my 77's Super T10 4 speed once. Wooo boy! Was that a mistake! Those syncrols did NOT like that super slippery gear oil. Dumped it out and back to Dino gear oil and all is good again.
Safety Car
Joined: May 2001
Posts: 4,759
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From: Fairfax Virginia
If it is old grease and such then hitting the shifter with a Hot Air Gun would help loosen things up a bit and make them move easier. I would also focus on the clutch release lever and the tube that attaches to the engine block for supporting the clutch pedal. A little heat and it might just wake up all the parts allowing the shifter to work better. On my shifter I have used Graphite spray like used on door locks to lubricate the mechanisms and it works great and won't freeze up like old grease can.
After this much time I personally would remove the U-Joints and half-shafts and re-grease them as well. Old grease is pretty useless after it turns hard. Again, Hot Air can help soften or liquefy the old grease and make it much easier to clean up from.
I would start at the brakes and work your way through the entire car looking for rubber parts that have to be replaced to make the C3 safe again. Sitting is a cars worst enemy...
After this much time I personally would remove the U-Joints and half-shafts and re-grease them as well. Old grease is pretty useless after it turns hard. Again, Hot Air can help soften or liquefy the old grease and make it much easier to clean up from.
I would start at the brakes and work your way through the entire car looking for rubber parts that have to be replaced to make the C3 safe again. Sitting is a cars worst enemy...
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From: Shamong, NJ
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From: Virginia
We tried synthetic in the Super T-10 in the Corvette vintage racer I crew on. We tore up a freshly rebuilt trans in one weekend of racing, the trans shop blamed the synthetic oil. It was about 5 years ago and forget exactly why they said not to us it, but I agree I think he explained it had something to do with being too slippery for the synchro to grab right? I had a Ford Toploader rebuilt about a year ago for a customer, and the shop I used said to stay away from synthetic too?
There was (for a time) a problem with some GL-5 synthetic oil, which would eat the yellow metal (brass syncros) in the transmissions. This should be fixed with reformulated oil, but perhaps that's what happened? Start reading here, and see how far down the rabbit hole you want to go.
https://bobistheoilguy.com/forums/th...is-safe.38972/
EDIT: This is specifically what I use. For GL-1, GL-2, and GL-4 applications, where GL-5 is "too slippery".
https://www.redlineoil.com/mt-90-75w90-gl-4-gear-oil
Some good info here, too (esp post #8)
https://www.gtoforum.com/threads/whi...-speed.133083/
Last edited by Bikespace; Feb 1, 2025 at 09:30 AM.
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