What Rear-End Ratio with 4L80E?
#1
TECH Apprentice
Thread Starter
Join Date: Jul 2003
Location: Houston, TX (La Porte)
Posts: 355
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
My setup (in sig) is complete, minus the pcm I'm waiting on from Allen.
Once I get the pcm in and its rolling, what gear ratio should I put in the rear-end to compliment the gear ratios of the new 4L80E transmission??
As of now, I have a 3.42 in the rear.
I do about as much highway driving as street driving.
Would 3.73 be okay, or would what I have now (3.42) be okay, or a 3.90, or what?
I heard the first gear is a BIAAA and doesn't shift till almost 60mph!
2nd Gear pulls very hard and is a lot shorter lived.
3rd & OD are the same ratio as 4L60.
Once I get the pcm in and its rolling, what gear ratio should I put in the rear-end to compliment the gear ratios of the new 4L80E transmission??
As of now, I have a 3.42 in the rear.
I do about as much highway driving as street driving.
Would 3.73 be okay, or would what I have now (3.42) be okay, or a 3.90, or what?
I heard the first gear is a BIAAA and doesn't shift till almost 60mph!
2nd Gear pulls very hard and is a lot shorter lived.
3rd & OD are the same ratio as 4L60.
#3
TECH Apprentice
Thread Starter
Join Date: Jul 2003
Location: Houston, TX (La Porte)
Posts: 355
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
Originally Posted by L-EATER
Well, I have only driven about 50 miles so (I have 3.73) I can't say for sure yet but I do know 3.42 will suck. If I had to change I would go with 4.10 but I do a lot of highway driving. If I were shooting for low et's I would go for 4.56. Just my opinion
I guess a 3.90 would be a good choice then? Right between 3.73 & 4.11.
I think that'll be the sweet spot to kinda keep highway driving mileage, yet good bottem-end as well.
HMMMMMMMM......with a 3.90, 2800 stall, I am just worried about traction.
I will have a posi, and a 12 inch wide tire (even though they're just Pirelli Scorpion Zero's), I wonder if I'll get a good bite on the street??
Maybe I should keep to the 3.73's?
#6
On The Tree
Join Date: Apr 2004
Location: Bloomfield, NJ
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
I know that on the Avalanche the guys with the 3.73 are always talking about how they want the 4.10 gears. With our trucks gas milage diffrence is almost non existant. I have heard difrences of maybe 15-30 miles a tank between the 3.73 and 4.10. In my opinion go the 4.10 and have the bottom end with the driveability on the higway of the OD tranny with the passing power on the down shift of the 4.10.
BTW I have a 4.10 reared AV and my bro has the 3.73. So I am talking from experience. In the avalanche club it is always talked about and the consensus is 4.10.
Hope this helps
Bonedog
BTW I have a 4.10 reared AV and my bro has the 3.73. So I am talking from experience. In the avalanche club it is always talked about and the consensus is 4.10.
Hope this helps
Bonedog
#7
TECH Apprentice
Thread Starter
Join Date: Jul 2003
Location: Houston, TX (La Porte)
Posts: 355
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
Just made the order for 4.10s!
They will be installed Monday PM
Allen's PCM should be delivered tomorrow if he comes through.
I cant freakin' wait!!
They will be installed Monday PM
Allen's PCM should be delivered tomorrow if he comes through.
I cant freakin' wait!!
Trending Topics
#10
TECH Apprentice
Thread Starter
Join Date: Jul 2003
Location: Houston, TX (La Porte)
Posts: 355
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
Originally Posted by Yukonuba
Don't you need Nelson to input your gear ratio for speedo calibration? Or do you have LS1Edit? ![Huh](https://www.performancetrucks.net/forums/images/smilies/LS1Tech/huh.gif)
![Huh](https://www.performancetrucks.net/forums/images/smilies/LS1Tech/huh.gif)
Allen was notified right after I made my appointment at the diff shop and he will be sending the pcm out with the 4.10s already programmed in it.
I am in Houston, he's in San Antonio, UPS Ground = Next Day Delivery.
Speedo and shifts will be screwed up on the way to the shop to get my gears I guess, but so what, its only 15 miles or so.