Ideal Highway RPM's and Gearing For 37s

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Supercharged111

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Those were optional ratios that TCI automotive has. Their 6X trans is a 6 speed modified 4L80E with revised gear ratios and it is cool!

73 GMC 3/4 ton was supposedly equipped with the 2.75/1.57 planetary from the factory.

It was a camper special and it had shocks in the front of the bed too! No idea what those were about though!

Thought of that after I got post.
 

stutaeng

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Thought of that after I got post.
Same here...

Did you saw the 4L80e got modified as 6 speed? That guy from the Transmission Bench mentioned this on the rebuild video series that got from him. But didn't mention specifics. He did say the dragster guys have done this mod

I guessed you wouldn't have reverse(?), so not going to happen on our daily drivers, lol. Unless you cut a hole on your floorboards and do a Fred Flintstones reverse special, lol.
 

Supercharged111

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Same here...

Did you saw the 4L80e got modified as 6 speed? That guy from the Transmission Bench mentioned this on the rebuild video series that got from him. But didn't mention specifics. He did say the dragster guys have done this mod

I guessed you wouldn't have reverse(?), so not going to happen on our daily drivers, lol. Unless you cut a hole on your floorboards and do a Fred Flintstones reverse special, lol.

Yeah, but the shifts are so damn short I think it's worthless. Now a 4L80 with that 2.75 1st I think would be sweet. GM's 6L80/90 works because it has such a wide spread. The TCI 6 speed does not, those itty bitty shifts would only keep a high strung 4 banger happy.
 

stutaeng

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Um, I'm not familiar with the TCI 6 speed. I don't get to drive our passenger van with the 6.0/6L90e/3.42 much, but it feels different than my daily driver suburban with the 6.0/4L80e/4.10.

Not really a fair comparison because the gearing is different, different weights and aerodynamics and different trannies altogether. But do I prefer the 4L with the 4.10s. Maybe I need more miles on the other to figure it out?
Yeah, but the shifts are so damn short I think it's worthless. Now a 4L80 with that 2.75 1st I think would be sweet. GM's 6L80/90 works because it has such a wide spread. The TCI 6 speed does not, those itty bitty shifts would only keep a high strung 4 banger happy.
 
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