did I hear someone say beer? May I please have some?
Printable View
did I hear someone say beer? May I please have some?
Confirmed this the other day. All factory 80 gear sets have the same ratio's. Not sure what you have read but it is not true. The only way to do this is to buy a custom 400 gear set and then modify it to work in an 80. Also when doing this you will need to use an early front lube 80. I just did one last week and the sun gear supplied is from a Th400. I would like to see if I can get the manufacture of the gear set to use the later 80 gear set. This way it could be used in the center lube cases and also it would cut down on the machining I had to do to make it work! Just figured I would bump this one up to clarify. Vince BQuote:
Originally Posted by RedHeartbeat
trying to find the link. Steve (MisterP) must have seen it somewhere before, too. 4l60e, 4l65e, 4l80e - SilveradoSS.com
here... SMOKEmUP.com :: View topic - Th350-700R4 trans?
Not sure if these guys have the right numbers or not but I like the 1st gear they have listed for the 80e...4Lo.com :: Final Gear Ratio, Crawl Ratio, Tire Size Calculators
I looked at the links and outside MRP saying the motor homes are different I do not see the proof. The only gear set that I have seen in motor homes has a straight cut gear set. However the ratio of this set is the same as every other factory 80. The one thing that guys complain about with using straight cut gears is that they are noisy. With that being said I think that is why they used them in larger vehicles because noise was not a concern. Strength was. However the regular planets work just fine and have a very low failure rate.
Not to step on anybodies toes here but I confirmed my beliefs with a good friend that works in a reman facility for GM here in Chicago. They have been doing the 80's for GM for years and I believe his info is correct.
The ratio's for a factory 4l80e are as follows.
First 2.48
Second 1.48
Third 1.00
Fourth .78
Reverse 2.08
I didn't know there was that much involved with a 60e - 80e conversion. :sad: And what are the gear ratios of a 60e?
First gear 3.06:1
Second gear 1.63:1
Third gear 1:1
Fourth gear .70:1
Reverse gear 2.30:1
Why would they make the 80 with a lower first gear ratio if it was meant for bigger trucks? I understand the engines make more power but it would be much more efficient to have the higher ratio for more torque and easier pulling.
Because bigger trucks usually have lower gears stock and also won't put up with the massive gear split 1-2 that the 60/65/70 has. Same reason why the ratios of the 80/85 are better for acceleration when larger amounts of power are applied.