Unless you are rock crawling, off roading, towing heavy loads, hauling heavy payloads, drag racing, stop light warrior, want to be cool, go with big 35" plus tires, etc., you really don't need the lower gears and will most likely hurt your gas mileage.

 

Thanks to everyone for their comments!

 

In stop and go city/country driving, the gears will help your gas mileage a lot. Long Highway driving, yes, there will be a drop.
Don't forget the extra strain on your engine/transmission they will eliminate

 

I haven't done the gear change yet (although I need to since I have 35" tires) but I did get a quote from a local gear shop for about $1100 total to change front and back to 4.56. I think I have read on here before that was in-line with what others were getting it done for. I'll most likely wait until my factory warranty is up before I do the change.

 

I totally disagree...I have 33in tall (almost...32.7in tall) tires on my truck (305/35/24s) and 3.55s and my truck doesn't hunt for gears or anything like that. The excelleration is not bad at all (I do have a 5.4) and I get 14.6 MPG. Which is pretty decent for a Scew with tires and wheels that weigh 160lbs each.

Any savings at all you get in MPG with gears would never cover the cost of the gears themselves. I also think the gear change would be more important on a 4.6 truck than a 5.4...the smaller motor would benifit more from the gears than the stronger 5.4.

 

well, the overall point I'm trying to get at is this:

Has anyone ever done a gear swap and not been overjoyed with the benefits? None that I know of...

How often to people go to oversized tires, get very disappointed over the performance loss, then go to forums looking for ways to get their truck running properly again? quite often. (the computer chips forum is full of them)

This is just my experience from years of reading forums, be they chevy forums or ford forums.

If you go to larger tires without gears, and are comfortable with the way your truck runs, good for you.
If you think it is ******* afterwards, gears are the only way to fix it properly.


Yes, 33" tires are a small size jump from your stockers, but you WILL lose performance, so be prepared for it.

 

as for gears paying for themselves, although I never said it would, it 'is' possible, depending on the miles per year you drive, and under what situation they are.

These are totally fictitious numbers made up so the math can be done.

Say you drive city/country roads with very limited highway (like I do) for 15000 miles per year. If you get 14 mpg with your larger tires and stock tall gearing, with better gearing it's very possible to get another 1.5mpg from what I've read (in stop and go driving)

14mpg for 15000 miles = 1071 gallons per year
15.5 mpg for 15000 miles = 967 gallons per year

1071-967= 104 gallons per year saved.

104 gallons x $2.00 per gallon = $208 saved per year.

$1100 gear swap / $208 per year = a little over 5 years to pay for it, assuming gas prices stay the same, shorter if they go up.

Now most folks who have a more balanced mix of highway vs. city, no, they will rarely recoup the difference. But the point is, it 'is' possible if you keep your vehicle more than a couple years and live in the sticks. If you routinely lug loads or tow things, the fuel savings will be more pronounced.

 

A gear swap is a pretty expensive undertaking. $1100 for a 4x4 would be pretty cheap and alot of people like to add a limited slip at this time if they don't already have one. Finding a "qaulified " person to perform the swap is a whole other area altogether. Sure some are lucky to have a place close by but in my area atleast(southwest wisconsin) you could go 1 hour in any direction and still not find someone (independent shop). Sure you could go to the dealer but then you would be talking major money and that wouldn't include having to listen to all their crap why you shouldn't do a swap.

 

...ProComp 33s with a 3.55 LS.....and it searches for gears between 30 and 75MPH. It's definitely frustrating driving around town, and I don't live in an area with many hills. I'll be having precision 4.30 gears installed as soon as the wallet allows, hopefully within the next couple months. Still, the bigger tires provide a much more stable and enjoyable ride than the stock hankooks.

 

Gear Ratio Guide for Larger Tires:

http://www.4wheelparts.com/4wp/asset...gear-ratio.htm

 

Does anyone know if they have 488's for our setup? 8.8 rear and I guess the same for the front.

I have an XL with the 4.6 and LS rear. I will be doing some good heay towing with mine at some point. Also the performance part of the upgrade will be nice too.

Matt