3.55 to 3.92 gearing

[rhann87]

is there any real benefit to changing such a small ratio? after tuning and whatnot, the motor seems much more responsive and i dont have the lag and sluggishness that used to be there after adding the 35's and lift and whats the business with conventional differentials? i realize most of the modifications are purely based on uses of the truck, but i want to make sure im getting the most possible out of it. only 60k miles and i plan on keeping it till the wheels fall off. might as well do it now.

 

[Burla]

Huge jump of the line and better driving rpm's, drive around in tow haul for a while, it is kinda like that but better if you have the 6 speed. I can't even spin the tires with my 3.55's, my friends truck can do an honest toasty (no brakes) with his 3.92's.

More rpm's all the time, especially off the line.

 

[S0CAL]

I went 3:55 to 4:56 front/rear and dropped in an LSD on my 2010 6-speed. It is not even the same truck, and a total blast to drive. I let a buddy of mine drive it and he thought it was in 4Low, lol. This is my daily driver and my RPMs went up just to 2300 at 85 mph. I also run 35s. If you're thinking of swapping gears, I recommend at least 4:10s, with 35s. Like you, I don't plan on getting rid of this truck!

 

[Pull Ya]

I don't think you are going to see a significant change going from 3.55 to 3.92. I agree it would be better to go to 4.10 if your going to spend the money to change gears. You didn't mention if you had a 4x4 or not, if you do, you will find the price is going to be LOTS more.
Jay

 

[Graygoose]

I don't think you are going to see a significant change going from 3.55 to 3.92. I agree it would be better to go to 4.10 if your going to spend the money to change gears. You didn't mention if you had a 4x4 or not, if you do, you will find the price is going to be LOTS more.
Jay

Agreed...4.10's or 4.56...yes...3.55 to 3.92's, me personally wouldn't add the expense.

 

[smoothee]

I went 3:55 to 4:56 front/rear and dropped in an LSD on my 2010 6-speed. It is not even the same truck, and a total blast to drive. I let a buddy of mine drive it and he thought it was in 4Low, lol. This is my daily driver and my RPMs went up just to 2300 at 85 mph. I also run 35s. If you're thinking of swapping gears, I recommend at least 4:10s, with 35s. Like you, I don't plan on getting rid of this truck!

I've got to bite the bullet and pull the trigger on this! Just wish it was a diy'er kind of job.

 

[rhann87]

I don't think you are going to see a significant change going from 3.55 to 3.92. I agree it would be better to go to 4.10 if your going to spend the money to change gears. You didn't mention if you had a 4x4 or not, if you do, you will find the price is going to be LOTS more.
Jay

its definitely 4x4 and i did notice a significant price jump. my number 1 concern with changing gears to something higher then 3.92 is premature wear on the motor and transmission. ive talked to a ton of dudes who have done it and everyone speaks positively then next thing you know there replacing the motor at 160k, granted a lot of things could have caused it. paranoid i suppose.

 

[S0CAL]

I have yet to find someone who has regeared and later regretted it. Regearing when you have larger tires actually takes the wear OFF your transmission. The gearing is more efficient. 4.10 with 35s is near stock ratio. I have a table somewhere, if I can find it, I will post it.

 

[S0CAL]

Here it is!

 

[huntergreen]

I wouldn't bother changing gears unless your going up in tire size.

 

[Wild one]

I have yet to find someone who has regeared and later regretted it. Regearing when you have larger tires actually takes the wear OFF your transmission. The gearing is more efficient. 4.10 with 35s is near stock ratio. I have a table somewhere, if I can find it, I will post it.

You didn't talk to me then,lol. I went from 3.21's to 3.55's ,mine wasn't done to pull bigger tires though,i swapped for dragstrip numbers,but i'd never do it again.My milege took a noticeable hit at 75+mph ,plus my oil temps also went up. The truck was as fast with the 3.21's compared to the 3.55's,but now I blow through first and second almost to fast. If I didn't have a ****load of money ******* in this diff with a True Trac posi /welded on Illicit relocation brackets,and the new 3.55's,i'd be putting the original 3.21 geared diff back in

 

[S0CAL]

You didn't talk to me then,lol. I went from 3.21's to 3.55's ,mine wasn't done to pull bigger tires though,i swapped for dragstrip numbers,but i'd never do it again.My milege took a noticeable hit at 75+mph ,plus my oil temps also went up. The truck was as fast with the 3.21's compared to the 3.55's,but now I blow through first and second almost to fast. If I didn't have a ****load of money ******* in my rear diff with a True Trac posi /welded on Illicit relocation brackets,and the new 3.55's,i'd be putting the original 3.21 geared diff back in

ZOINKS!!

 

[69GWC]

What transmission do you have Wild one.

 

[crackerjack1957]

Got to be the 8-speed if he blows thru 1st & 2nd.

 

[Wild one]

What transmission do you have Wild one.

Somebody beat me to it,but mines the 8 speed,with a tranny tune done through my HP tune. My shift points are set at 6100.

 

[Wahrsuul]

He did go up on tire size. 35"

 

[RLJ10X]

Gearing down is increasing the mechanical advantage of the drive line, thus reducing wear on transmission and engine.

I’ve gone from 3.55 to 4.10. I highly recommend doing this. First gear in the 5/6 is too tall. The truck just lugs and moans with 3.55s. The truck is much happier with 4.10s.

I’d sell my truck before I’d drive 3.55s!

 

[S0CAL]

Gearing down is increasing the mechanical advantage of the drive line, thus reducing wear on transmission and engine.

I’ve gone from 3.55 to 4.10. I highly recommend doing this. First gear in the 5/6 is too tall. The truck just lugs and moans with 3.55s. The truck is much happier with 4.10s.

I’d sell my truck before I’d drive 3.55s!

I could not agree more. A totally different experience and a complete joy to drive.

 

[Wahrsuul]

I have the 3.55s with the 5spd, haven't noticed the engine "lugs and groans". Heck, right now I'm using a PC in Eco mode to see if it'll improve MPG, so take offs are slower than normal, and the engine pulls along fine.

Now if the SWAMBO has her way and we get a TT, I might consider gearing down a bit to add some towing capacity. But since I wouldn't be changing tire sizes, I wouldn't go below the 3.92. Besides, I could probably just find one in a salvage yard a pull the whole rear end and swap. Make everything easier.

 

[rhann87]

Gearing down is increasing the mechanical advantage of the drive line, thus reducing wear on transmission and engine.

I’ve gone from 3.55 to 4.10. I highly recommend doing this. First gear in the 5/6 is too tall. The truck just lugs and moans with 3.55s. The truck is much happier with 4.10s.

I’d sell my truck before I’d drive 3.55s!

looks like i have some homework to do. any recommendations? i tuned the motor with Hemifever just a week or so ago and i seem to be doing better, but i find myself getting caught between gears with less power. dont get me wrong its a significant improvement over the stock program and at WOT its a marked improvement.