The Stovebolt Site Forums The Shop Area Driveline 58 PG

on my 1958 powerglide the tranny shifts a little too late i think , it shifts around 35 mph, by my speedo , is that normal ??? it down shifts just fine , i have checked the fluid ,its fine, somone fill me in please

thanks

Do you have 2-speed Powerglide, which I do not see listed in the 1958 truck specification manual (but was available in later years), or do you have the 6-speed Powermatic that was available in 1958 trucks?

What color ID plate (and ID code) is on the transmission?

Yes its a 2 speed

Accarding to the '59/60 Suppliment, the upshift points w/235 and 3.36 axle are; Throttle Closed 12-15 mph, Detent Touch 27-44 mph, Through Detent 44-49 mph.

Sorry i dont undersand all that

At engine idle it will up shift from 12-15 mph
moderat throttle opening will upshift from 27-44 mph
At WOT (full throttle) it will upshift from 44-49 mph
That is all with stock 3.38 axle ration & tires that are the same rolling circunfrence as stock.

Ohh ok i see now thanks, , moderat throttle 27-44 seems high 44,wow maybe mine is right on then, ,is there a way to chang it?

Change the length of the throttle linkage from the carburetor to the transmission. I don't recall which way to move it, but lengthening the linkage will move the shift point up or down, and shortening it will have the opposite effect. DO NOT GO FOR AN EXTREMELY SOFT SHIFT! It will cause the clutches to slip and burn. A powerglide has two shift speeds- - - -too low and too high!
Jerry

Because a powerglide is essentially missing first gear compared to a 3-speed, don't concern yourself with it shifting too high. As long as it shifts well and isn't over-revving the motor it's not a big deal.

thats what i am affraid of ,, seems to me it should shift sooner ,, but could be me , i drove it all weekend and seems like i could play with gas and make it shift sommer , by revving it and when i want it to shift just let off a tiny bit , or anyway seems like ,,,

thanks

I always thought the PG basically missed 2nd gear. That's why the waited a bit later to shift.

Either way, they do delay shifting a bit longer than most automatics.

Sounds as if it could be operating as designed. It's a big jump from lo to direct, if it shifts upshifts any sooner it will have to downshift again with just a slight load or throttle increase. Every Power glide I've ever driven sounded like a s screaming jet right before WOT upshift.

Thanks good to hear,, i was hoping it wasnt bad,

Thanks