Do anyone have an idea on about how much it would cost to change a rear end unit in a 04 Dodge 4x4. I have the 3.55 and I want to go to a higher ratio gearing.I don't pull enough to need this rear. And it has a Hemi anyway so what do you think.

 

I'm a little confused as to how you want to change the gearing. You say you want a higher gear ratio, but then you say you don't pull enough to need the 3.55 rear end. I'm not trying to be a smart-**** at all, I just want to be sure of your motive before I offer any advise.

If you are going to want more MPG, I really don't think a gearing ratio would be a good choice. First of all, you have a 4x4. Because of this, you will need to change the front and the rear or you'll damage the system. They both have to spin at the same speed to prevent binding. I think the latest estimate on having someone to do the work for you is $1K+ depending on the shop. You'll never recoup the money you invested in the gearing or at least not for a long, long time.

I have the 3.55 rear and find that it is a good combo for the amount of towing I do and the mileage I expect. I'm getting about 12.5-13.5 in constant stop and go driving and 16-18 mpg on the highway depending on how fast I go and the terrain I'm in. I've found the biggest factor in getting good MPG is driving habit. I try not to let the RPM's get above 2200.

Last week, we traded in my wife's 2003 Expedition EB for a 2005.5 VW Jetta. We went from 8-10mpg in town and 15mpg highway to about 20mpg in town and 30mpg on the highway. Not to mention our payement and insurance went down. We still have my truck if we need to haul/tow something or need the interior space.

 

In the general ram forum..there is a post called "Rear end gears"....someone posted in there the differences for each gear.....showing mpg and so on for each gear ratio....some good info.

 

If i'm not mistaken a "higher ratio" means a smaller "number". Like 3.55 is a higher/taller gear ratio that 3.92 or 4.10.
The "bigger" numbers like 4.10 and 4.56 will yield more low end power and a lower top speed at higher rpm while the "smaller" numbers like 3.55 and 3.92 will have a higher top speed at a lower rpm but less low end power.

http://www.4lo.com/calc/geartable.htm

 

I've heard it both ways, that is why I wanted clarification as to what he was trying to do with the gear swap.

Either way, I don't think it will be beneficial, cost wise.

 

I'm getting rid of my boat this year. So I won't be pulling anything ,so I just want to get the best Mileage I can out of this tank. Maybe I can find someone who wants to trade my 17 in tires for there 20 in tires.That'll be a start. I know that by the middle of summer gas is going to be over $3.00 a gallon. So if I can't increase my fuel mileage I think I'll trade off the Hemi and get another PT Cruiser. The first one get's 22 local and 32 on the highway, The only reason I drive the Hemi is that we made a show car out of the PT and we only use it for major street rod events and PT cruiser shows. So far we have won 41 trophys with it..And now that a Chrysler Dealer is giving our club discounts on new non Dodge products .that includes 20 per cent on parts and service... I can't loose.