Rancho lift/Front Diff

[Hummerboy]

Just got my h3 back today. Mounted 37x13.50 mud grapplers on it. I went with the rancho lift and the daystar 1 inch body. I'm now on the fence about a PCM tune but was wondering what options I have for a new front diff to get better gears to help turn the tires. I'm not interested in a SAS just a bigger front diff just wondering my options and what gears would be recommended. If I get a new front diff will the PCM tune be for nothing? just wondering if I should save my money now and go with the bigger diff and skip the tune or if they will both help.

Never posted pics so not sure how they'll come out what's pictured is 06 hummer h3 lux with 4 inch rancho lift 1 inch daystar body lift 37x13.50r17 nitto mud grapplers rims are pro comp 7036 17x9 and lastly Fox shocks on all 4 corners.

 

[cgalpha08]

Do you have an adventure or non adventure model (rear locker or not)? If you have the rear locker from the factory then you already have the biggest gear ratio in the front that you can have, 4.56. If you dont, then you can regear to that. Since you do not want to do the SAS, then your other option is a custom IFS set up like what bebe has. The idea of putting a bigger front diff in and keeping as many OEM parts as possible has been tossed around several times and a solution hasn't been found.

In summary: If you dont have 4.56 gears, re-gear to that (cheapest option). Or do what bebe did and do a custom IFS long travel setup with a larger diff.

 

[Cajun_Tiger_Hummer]

Nice rig, how's it drive with those 37" tires? I've been looking at doing the same but want to go with MTR Kevlar's b/c they are one of the lightest tires on the market.

 

[amrg]

Love the truck, looks great. 06 H3 comes with 4.56 gear, its not possible to regear it for the bigger tires (as one member have told you). Unless you have an Alpha, which was introduced in 08 (comes with 4.10 gears).
Now that you have a rancho, you have more space to fit a bigger diff, offcourse ur talking custom stuff.

 

[Hummerboy]

Non adventure unfortunately.... So I can regear to 4.56 in the front? Also would a custom IFS job work with a rancho?

 

[poweraidon]

That looks so good [emoji7] how much was everything?


Sent from my iPhone using Tapatalk

 

[cgalpha08]

Non adventure unfortunately.... So I can regear to 4.56 in the front? Also would a custom IFS job work with a rancho?

Your best best IMO is to regear the front and rear to 4.56, and get a PCM tune, that will help some.
The custom IFS will basically negate anything that rancho has done to the front since you are going custom, the rear will depend on how much higher you decided you want the front to sit over stock.

 

[Hummerboy]

Would it be possible to drop and alpha front diff in? May sound dumb just wondering my options because I plan to have it a while

 

[Hummerboy]

It rides great so far much smoother than with my t bars cranked. Only driven it for a day so time will tell

 

[Panzer07]

I Like It Very Much. What rims are You running ?!!


Sent From Someone Else's iPhone 'Cause I'm Too Broke To Own One.

 

[cgalpha08]

Would it be possible to drop and alpha front diff in? May sound dumb just wondering my options because I plan to have it a while

Yea you can drop in an Alpha front diff, make sure the gearing is that same as the rear, the only real difference is that it is cast iron vs aluminum. You can't get a higher ratio than 4.56 in an alpha diff either.

 

[Hummerboy]

So with 4.56 what exactly would change? Would I be able to travel at highway speeds? Sorry if my questions seem redundant with so few running 37s I'm just trying to gather the most info I can before I mess something up

 

[06 H3]

Nope 4.56s are stock if you have an I5 adv package or not. If you have an I5 you cant regear any lower only the V8 guys can regear because they are at 4.10s. They can go to 4.56s every Inline 5 has 4.56s stock

The difference is gearing from adv. to non adv is in the Tcase

 

[Hummerboy]

I Like It Very Much. What rims are You running ?!!


Pro comp 7036

 

[cgalpha08]

Nope 4.56s are stock if you have an I5 adv package or not. If you have an I5 you cant regear any lower only the V8 guys can regear because they are at 4.10s. They can go to 4.56s every Inline 5 has 4.56s stock

The difference is gearing from adv. to non adv is in the Tcase

Whoops, my bad on that lol, thanks for the clarification.

 

[Hummerboy]

06 h3 is a PCM tune my only route then unless I get into serious mods like Bebe? I'm not against it but just getting the rancho that would be throwing money down the drain to get rid of it now.

 

[06 H3]

no prob. Your lucky, you have the V8 you can run 4.56s with the V8 and a rancho lift 37s and still have it run down the freeway at 80 with no issues. Thats part of the reason for my SAS. Regearing to 5.13s there is no feasible way to regear and get a bigger diff in the front. If you do you will spend a ton of money unfortunately.

Hummerboy PCM it, it will help but without dropping a ton of money on the ifs the cheapest way is to SAS cheaper then that is to pull the front diff regear the rear to 5.13s or 5.38s and go 2wd lol but you would never live that down...

 

[Hummerboy]

PCM it is... I thought it would be as easy as finding a bigger front diff drop it in and keep going haha I guess if it was only that easy... and as we've all learned nothing is ever that easy with a Hummer

 

[derian06]

06 h3 is a PCM tune my only route then unless I get into serious mods like Bebe? I'm not against it but just getting the rancho that would be throwing money down the drain to get rid of it now.

Wait 4 weeks and i'll buy it from you


Sent from my iPhone using Tapatalk

 

[Bananatank]

Wait 4 weeks and i'll buy it from you


Sent from my iPhone using Tapatalk

Lmao


Sent from my iPhone using Tapatalk

 

[Cajun_Tiger_Hummer]

Hows the acceleration with the 37's? On the highway and in town driving?

 

[Hummerboy]

Very very slow but honestly I thought it was slow to begin with. I bought it to off road not to have a sports car so it doesn't bother me


Sent from my iPhone using Tapatalk