have a 2000 4x4 auto with 3.55 gears, truck has zero power to pull. i am running 285 tires on factory rims and truck is gutless, runs perfect but just wont giddyup. rode in some friends trucks like mine and it will snap your neck,i would hesitate to pull out in traffic on this one. runs down the road ok but just doesn't seem to have the go to it. when i bought the truck, it had the factory sized tires on it and it was great- i went up a size or two on the tires and it is embarrasing now. was thinking about putting in 3.73's at least. a new neighbor moved in down the road and stopped to introduce myself to him the other day and found out he was a dodge vp over parts in the area....he said he doesn't know why dodge ever put 3.55's in this type truck. any thoughts out there? how do you find out what axles you have and where would be the best place to order gears for ring and pinion?
thanks
bill

 

With an auto, you'd have a D60 up front and a D70 out back. 3.55's are a good ratio for these engines. Generally, you won't need much more gear. I'd say make sure your tranny is in good shape, and get a tuner or box for your truck. For the price of swapping gears front and rear, you could buy some decent power, which would be more dramatic.

 

tate-
i bought the truck about a year and a half ago, and i noticed it had a badge on the tranny bellhousing that the trans was replaced by the dealer in 05'. i was looking into a programmer, just haven't decided what kind to get. the truck is basically stock and is used for everyday driving. i have no pans on making it a monster or anything. doesn't feel like the trans is slipping or anything, just doesn't seem to have any giddyup. if you stomp on the right pedal, it doesn't really want to wind up quick enough. if that sounds right.....thanks
bill

 

A valve body and torque converter might be a worthwhile upgrade for you. You won't be making more power, but you will get it down to the ground better, so it will feel better. But to be honest, I'm not to up on auto trannies, so hopefully others will jump in.

Do you have gauges? The main 3 (and a tranny temp gauge) will help you diagnose this problem. Low fuel pressure will cause poor power, a boost leak would show up in low boost, and higher EGT's. Excessive tranny temp would show slippage.

 

Get and Edge EZ or Quad box. That'll take care of the low power and don't cost an arm and a leg.
Like Tate said a good VB & TC will help a lot.

 

I was thinking about changing gears in my truck to help with fuel milage. My younger brother has a 94 3/4 ton gasser 4x4 without knowing would they have the same size axels from a gasser to the diesel? His are 3.55 mine are 3.73 any advice or help is appreciated.

 

The gasser is gonna have Dana/Spicer rears and your 06 had AAM rears. Won't work. Take your truck to a shop that does rears and get a price on the gear swap. I't should be about $1500-$2000, those are high but with parts and labor sounds about right.