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Who has 4.56 Gears in there 8 speed transmission?


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Posted

I have a customer with the 8 speed in their 16' Escalade. Originally did 4:10 gears and we have since upgraded to 4:56. They are much happier with the vehicle-

It's set up on 33x12.50R20 wheels/tires(heavy beadlocks & M/T tires). Granted the SUV is running a twin turbo set up, it was a night a day difference changing the gears. 

 

4:56 is 110% the way to go with your tire size. You will be very happy with the truck

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Posted
2 hours ago, SuthrnZ71 said:

Would 4.88s be overkill?

In the 4l60e days that would have been the gear of choice for that size tire, but with today's lower ratio 1st gear transmissions, 4.56 should be fine.

Posted

good call on the change to 4.56

 

Like I said I don't know how they are with the 8 speed but I love em in my 6 speed

 

If the above is correct about the final drive ratios in the 8 & 6 being the same then like I said your rpms are gonna be up above 2000 cruising down the hwy. 

 

1718-DEF7-E264-4-B32-A8-EA-ADD4-E8758-F6

Posted
11 minutes ago, Jacoby said:

good call on the change to 4.56

 

Like I said I don't know how they are with the 8 speed but I love em in my 6 speed

 

If the above is correct about the final drive ratios in the 8 & 6 being the same then like I said your rpms are gonna be up above 2000 cruising down the hwy. 

 

1718-DEF7-E264-4-B32-A8-EA-ADD4-E8758-F6

Off topic, but I noticed that your ABS and Stabilitrak are off. Did you pull fuse #25, tap into the wheel speed sensor, use the Shane Hinds cable...?

And where did you get a speedo that goes up to 200mph! =)

Posted

Is there a recommended brand of gears for a 2019... and what would i expect to pay for them?

Posted
4 minutes ago, Mileguru said:

Off topic, but I noticed that your ABS and Stabilitrak are off. Did you pull fuse #25, tap into the wheel speed sensor, use the Shane Hinds cable...?

And where did you get a speedo that goes up to 200mph! =)

My right front wheel speed sensor had taken a dump at the time, that's why the lights were on.  Ive since replaced it and no more lights

 

I have a Canadian truck hence the speedo.  200kmh is 125mph.  The light on the dash was swapped from KMH to MPH

 

If you look at my coolant it reads Celsius instead of Fahrenheit and my oil pressure reads KPA instead of PSI

Posted
1 minute ago, BillyDee said:

Is there a recommended brand of gears for a 2019... and what would i expect to pay for them?

Depends what size you go with.  Yukon is the only brand that made anything bigger than a 4.10 for my truck so that's what I had to go with.  4.10 and under there are a few companies that make them

Posted
8 minutes ago, Jacoby said:

My right front wheel speed sensor had taken a dump at the time, that's why the lights were on.  Ive since replaced it and no more lights

 

I have a Canadian truck hence the speedo.  200kmh is 125mph.  The light on the dash was swapped from KMH to MPH

 

If you look at my coolant it reads Celsius instead of Fahrenheit and my oil pressure reads KPA instead of PSI

I'm thinking of wiring in a switch to fully disable/enable Traction Control, Stabilitrak, and ABS to have more fun with my supercharger. Did you notice a difference when your wheel speed sensor was out and the Stabilitrak and ABS were out?

 

I've heard that disabling Traction Control and Stabilitrak with a switch or fuse (not just with the console button that allows Stabilitrak to come back on at 35mph) helps the lifted trucks with bigger tires and lower gears too.

Posted
23 minutes ago, Jacoby said:

Depends what size you go with.  Yukon is the only brand that made anything bigger than a 4.10 for my truck so that's what I had to go with.  4.10 and under there are a few companies that make them

I was thinking along the lines of 4.10 for 35" tires

Posted
4 minutes ago, Mileguru said:

I'm thinking of wiring in a switch to fully disable/enable Traction Control, Stabilitrak, and ABS to have more fun with my supercharger. Did you notice a difference when your wheel speed sensor was out and the Stabilitrak and ABS were out?

 

I've heard that disabling Traction Control and Stabilitrak with a switch or fuse (not just with the console button that allows Stabilitrak to come back on at 35mph) helps the lifted trucks with bigger tires and lower gears too.

Truck ran fine.  Only thing was my cruise control stopped working.

 

I do some mudding every now and then and I just turn traction control off.  I can slip and slide all I want and I don't get any adverse reactions

Posted
5 minutes ago, BillyDee said:

I was thinking along the lines of 4.10 for 35" tires

Im not sure if the 19's use the same rear end as the 14-18.  For a 4.10 I'd check out G2 or Yukon.  They seem to be the go to for gears

Posted

I'm no gear expert but found a calculator to compare ratios and tire size: http://www.dieselhub.com/tech/ratio-tool.html

 

"Original" is based on a factory 32" with a 3.42 axle and the 8L90's 8th gear ratio of 0.65:1. Variation 1 is with a 38" tire and a 4:10 axle. Variation 2 is the same but with a 4.56 axle. All are at 75 MPH. Looks to me that 4.56 is the way to go.

 

 

Screenshot 2019-05-07 at 5.36.53 PM.png

Posted

Sorry for the non response. Im a 3rd shifter..

You guys are a big help. Im definitely going 4.56 and will report back when its done. Im scheduled with East Coast Gear on the 24th for the install.

Posted

Awesome Jeep, what are the specs? Is it stock or are your running the DeWalt 18v mod? Just kidding.

 

Guy's are using 4.56 gears with 33" tires here. I would probably do the lowest ratio I could get, being the 4.56 looking at that freakin' monster of a truck. Can you turn your wheels while driving or will your tires rip your bumper off? Looks amazing, first K2 I have seen on here with anything larger than a 35" tire. 

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