78 speedometer gear
How do you know which gear belongs in the tranny for the seedometer to be correct. Mine is to fast.
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Re: 78 speedometer gear
Larry-----
LOTS of factors come into play to determine what the correct gear for your application is. IF you are using stock OD tires and you can tell me what rear-end ratio and transmission is installed in the car, I can tell you what the correct gear should be.
If you are not using stock OD tires, the best thing to do is to determine what your TRUE speed is at several INDICATED speeds and compute what percentage "off" you are. Then, you may be able to install a DRIVEN gear that corrects for it. You can accurately determine TRUE speed by using a GPS.In Appreciation of John Hinckley -
Re: 78 speedometer gear
355 gears, 350 tyrbo tran, 225-70-15 tires, which gear for the speedometer to be right? it has a 19 tooth in itComment
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Re: 78 speedometer gear
Larry-----
According to my information, you should have an ORANGE 8 tooth DRIVE gear (the gear inside the transmission and if you currently have a "natural" colored 19 tooth DRIVEN gear installed, then you almost certainly have the correct DRIVE gear) in conjunction with a SILVER/GRAY 22 tooth DRIVEN gear. So, try the SILVER/GRAY 22 tooth DRIVEN gear. It's GM #3987922.In Appreciation of John HinckleyComment
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Re: 78 speedometer gear
Thanks Joe
I will let you know, will order tonightComment
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Re: 78 speedometer gear
the SILVER/GRAY 22 tooth DRIVEN gear GM #3987922, this no is for a 4 speed, will it work in an autoComment
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Re: 78 speedometer gear
Larry-----
The GM #3987922 IS part of a series used for 4 speed transmissions, both Muncie and BW T-10. However, it's also used for THM-350 automatic transmissions and Powerglide transmissions, too. It's NOT used for THM-400 or THM-700R4, though.In Appreciation of John HinckleyComment
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