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-   -   Regearing? (http://www.elcovaforums.com/forums/showthread.php?t=42292)

tyler1bo 01-31-2012 01:09 AM

Regearing?
 
Alright guys I need to regear my '08 SUT from the stock 3.73's..what would my best option be? Keep in mind that mine is the new 6-speed. My 3.73's just aren't strong enough to push 38's with 20's. Help please!

EuroHummer 01-31-2012 01:16 PM

Re: Regearing?
 
I went with 4.56s. I have 37s. With the 38s, you might want to go to 4.88s. Depends on how much you travel on the highway, and how much time offroad.

tyler1bo 01-31-2012 02:28 PM

Re: Regearing?
 
Right now it's more highway than offroad..my truck is about 90% street 10% offroad

guruerror 01-31-2012 05:28 PM

Re: Regearing?
 
Check out this 'gear calculator': http://www.4lo.com/calc/geartire.php

My 05 had 4.10s stock, when I move to 37s it started to drag ass, so punched my info in the 'calculator' to find out what gears would give me an effective ratio closest to stock.

The tire size change had reduced my effective ratio to 3.88 and the calculator indicated that 4.33s would put my effective ratio back up to the stock level. Since they don't make 4.33s I went to the next 'lowest,' 4.56s, and have been a happy camper every since.

tyler1bo 01-31-2012 07:03 PM

Re: Regearing?
 
It's showing me at 4.05..do you think 4.10's would be enough?

charles06 01-31-2012 07:03 PM

Re: Regearing?
 
I did 4.88's with 38" Toyos and it made a HUGE difference. That gearing works well with my new 40's as well.

tyler1bo 01-31-2012 07:08 PM

Re: Regearing?
 
Does yours have the 4-speed tranny or 6? Mine has stock 3.73s with a 6-speed. I punched my numbers in the gear calculator and it's saying I should move to 4.10s

2010_5thgen 01-31-2012 07:27 PM

Re: Regearing?
 
those 6 speed tranny's are crazy. i drove my buddies 08 yukon denali and that thing was just stifting like crazy. seemed like at cruising speed, it didnt know if it wanted to be in 5th or 6th.

regearing should help with MPG and the pickup right? ive noticed mines a bit sluggish off the bat and it stays in 2nd gear longer than it used to. is this normal with a lift and larger tires?

tyler1bo 01-31-2012 07:42 PM

Re: Regearing?
 
Yes it should help both MPG and pickup..surprisingly though my I reset my CPU after the lift and I'm currently getting 11.5 hwy/city driving, which is brilliant for me. I would like to regear though because my shifting is getting sh*tty and slow, feels like my tranny is slipping. I took it in the shop to see if my tranny was okay and I think it's just my gears not being strong enough..I slip from 1st to 2nd kinda..

charles06 01-31-2012 08:11 PM

Re: Regearing?
 
I have the 4 speed.

I always wonder how accurate those MPG readings are after I've changed the gearing, tire size, and used a tuner.

tyler1bo 01-31-2012 08:21 PM

Re: Regearing?
 
I still think it's pretty close..course I'm not stompin on it either..just cruisin mostly besides hwy. I think at worst i'm getting 10

charles06 01-31-2012 08:49 PM

Re: Regearing?
 
Yeah, I try not to get too caught up in it. I just tell myself I'm getting more than what shows. Haha

guruerror 01-31-2012 09:04 PM

Re: Regearing?
 
Quote:

Originally Posted by tyler1bo
Does yours have the 4-speed tranny or 6? Mine has stock 3.73s with a 6-speed. I punched my numbers in the gear calculator and it's saying I should move to 4.10s

I've got the 4-speed...

If the calculator says 4.05-4.10 then the 4.10s would put the performance closer to what you were used to before the tire size change. But to really get things back in order you should also use a programmer to let the 'computer' know that you've change the tire size and gear ratio; that should get your shifting and whatnot straightened out.

tyler1bo 01-31-2012 09:56 PM

Re: Regearing?
 
I have a programmer. I'm using a superchips flashpaq at the moment.

guruerror 01-31-2012 10:23 PM

Re: Regearing?
 
You should be good to go then...looks like the Flashpaq allows you to adjust tire size and gear ratio just like my Cortex.

With some 4.10s and a re-program you should get your pep back, your shift points and cruising speed will be closer to normal, your speed-o will read correctly, and you may even get a whole MPG out of it.

tyler1bo 02-01-2012 02:05 AM

Re: Regearing?
 
Not a WHOLE MPG!!!! ;) Yes it's either 4.10's or 4.56's..

Bimmer9938 02-01-2012 09:47 AM

Re: Regearing?
 
Quote:

I did 4.88's with 38" Toyos and it made a HUGE difference. That gearing works well with my new 40's as well.


How much did it improve your MPG?

2010_5thgen 02-01-2012 02:06 PM

Re: Regearing?
 
so 4.10 or 4.56 are good for 38" tires? i think im going to start with a tune, but im gonna take mine to a shop that has a AWD dyno to do a custom tune.

tyler1bo 02-01-2012 04:40 PM

Re: Regearing?
 
A custom tune will probably be the best. You probably need to look at 4.56 to 4.88 gears. I believe you have stock 4.10s. I think I may go with 4.56 because I'm not sure 4.10s will be that much of a difference. Do any of y'all know a good place to find gears?

guruerror 02-01-2012 05:30 PM

Re: Regearing?
 
www.trailduty.com...more specificially: http://www.trailduty.com/index.php?c...0cd11dd8a5fc9b


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