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69GMCLonghorn · 01-28-2014, 03:37 PM

It wasn't meant to be a usable gear all the time, just to get you rolling with 150 tons behind or in your truck. I like it for crawling along in this great city of LA to avoid slipping the clutch. Between the various transmissions, you won't have a different top gear. They were all 1:1. They didn't know the meaning of OVERDRIVE back then. You'd have to ditch the 530 gears for something more highway friendly. The only difference from one tranny to the next in that generation are the other gears. There was an SM420 which had an even LOWER granny gear. Then some of the newer but still pre-O/D ones has a higher and more usable granny gear.

01-28-2014, 03:37 PM	#4
69GMCLonghorn Registered User Join Date: Dec 2006 Location: Porter Ranch, CA Posts: 978	Re: 4 speed question It wasn't meant to be a usable gear all the time, just to get you rolling with 150 tons behind or in your truck. I like it for crawling along in this great city of LA to avoid slipping the clutch. Between the various transmissions, you won't have a different top gear. They were all 1:1. They didn't know the meaning of OVERDRIVE back then. You'd have to ditch the 530 gears for something more highway friendly. The only difference from one tranny to the next in that generation are the other gears. There was an SM420 which had an even LOWER granny gear. Then some of the newer but still pre-O/D ones has a higher and more usable granny gear.