i have a 94 2500 4x4 ctd with 315/75/16 and with 4 10's i was thinks about gearing it a little lower to make for for the larger tires i do mostly around town driving but i dont want to make it to bad on the highway is there gears i can go with to give me a little better mpg and a little more take off power i get around 17mpg mostly city now
thanks ronnie

 

4.56's are the next step up and would give you back some low end punch...... should help your around town mileage as well...... me personally i have 3.73's (i think) and im running 315/70/17's on my truck and im gonna see where my mileage goes seeing as i do 90% highway driving......

 

Id leave it as is...

you will have super low end with the 4.56 gearing ratio, but ur top end will really stink due to you running out of RPMS. unless of coarse you get a GSK in there... 4.10s and 35's are a sweet combination, right at about 75 mph at 2000 rpms, but the tradeoff is the slightly less lower end. Why not go ahead and loosen the starwheel, or bump the fuel plate forward? Get some gauges first tho...

PS NH redneck, our trucks came only with 3.55 or 4.10 unless of coarse you have aftermarket gears or another rear end... Easy way to tell 60 mph at 2000 rpms you likely have 4.10s, 70 plus at 2000 rpms, u have 3.55s

Rick

 

gotcha TX..... looks like im in the 3.55 crowd then.... right now with the mods in my sig i can tell with the town driving that i need to use a lil more power to get moving, but the drop in rpm at highways speeds totally makes up for it all...... im sure that the 3k GSK will really help things out a bit....

 

4.10's on the highway is no fun.
Im trying to find some large rims so I can put on big tires without all the sidewall flex you get from the 'balloon-look'
Stuff aint cheap though

 

i need to figure out the star wheel thing supposly the truck has a differnt fuel plate on it ,if this was a gas engine i would know alot more about it

 

At 60mph I am running about 2100rpms. I have a 4.10 and 285/75/16s. Is something wrong with this picture?