I am trying to figure out if i have 3.54 or 4.11 gears in my 1998 dodge ram 2500 4x4 auto tranny, @ 65 mph I am turning 2200 rpm. I have 285/ 75/ 16 all terrian tires, And is there a # in the Vin # to tell what gear it has. I still have the window sticker from the dealer and it is no help. thanks

 

look in the glove box it should tell somewhere what gears it has.

 

its not in the glove box either. I wish it was.

 

On my '98 the option label is on the under side of the hood.
With stock 245/75s and 3.54 gears I believe the RPM@70 is ~2000.
Did you have the speedo recalibrated?
From what your stating it sounds like you might have 4.10s, but kinda odd that the window sticker wouldn't point out 4.10s.
Any chance your torque converter isn't locking up?

 

No i need to have it recalibrated, is that something that has to go to the dealer to have done, the converter is locking up. i am going outside to see if its under the hood. thanks for the advice...

 

Thanks its under the hood its has 3.5 as gear ratio so I am assuming it has 3.50's in it

 

I think you have 4.10s. I have 265/75r16 tires and at 65 I'm turning about 1900 rpms. Best way to tell is to pull the rear cover and look. It is probably due to have the gear oil changed anyway.

 

Id guess 4.10's also with that engine speed. I show 2200 at 70 on mine

 

Get your VIN#, call your dealer, his computer will have a "build sheet" that will tell you everything about your truck, from the color (just in case you were wondering ) to the diff ratios.

 

Thanks guys for all your great advice i sure appreciate it !

 

You could either have 373's or 410's if your running 2200 at 70...

 

3.73 were not a option in 98, only 3rd gens.

 

Sounds like 4.10s. my 03 runs about 2200 at 65 (I think). Either way, it runs faster than my brother's, with 3.54's.

 

Definitely the 4.xx gear in your truck. I just picked up a '95 last night and at 70mph I was below 2k rpm, more like 1800; didn't really set there and try to figure out the tach increments.

My 01.5 also has the 3.54 but this '95 seems to have an even lower rpm at 70, perhaps b/c it's an auto and the 01.5 is a 6spd ?

 

That is true.....the autos have a higher OD gear than the manual trucks so they will rev lower in OD. My 94 auto and 98.5 manual had the same height tires and both had 3.54 gears but the auto was doing 75 mph at 2000 rpm while the stick is 70 mph at 2000 rpm.