2nd Gen Non-Engine/Transmission Rear End?

[TDeSteuben]

just picked up my truck,,, its a 2001 2500 4x4 short bed 6-speed diesel,,, can anyone tell me what rear end gear ratio is in it? i doubt its a 4. 10,,,, is it a 3. 73? could it be lower? any help is appreciated

 

[Cummins Thunder]

Look in the glove box. You should see a white sticker with that info and more.



Edit: I am pretty sure you could get the 3. 54 with the 6spd/HO

 

[BDaugherty]

Factory gear offerings were 4. 10 and 3. 50 for 2nd gens. If your RPMs are around 2500 @80MPH then you've got 4. 10s. If you're turning about 2000 @80MPH, then you've got 3. 50s.

 

[kenny61]

Easy way is jack up rear see how many times tires go around vs one spin on drive shaft. Leaves out chance that owner changed gears

 

[Cummins Thunder]

Factory gear offerings were 4. 10 and 3. 50 for 2nd gens. If your RPMs are around 2500 @80MPH then you've got 4. 10s. If you're turning about 2000 @80MPH, then you've got 3. 50s.

4. 10, 3. 73, 3. 54

 

[cojhl2]

Easy way is jack up rear see how many times tires go around vs one spin on drive shaft. Leaves out chance that owner changed gears

Also, mark where tire is on ground, push pickup back 1 tire rotation.



How many times drive shaft rotated is the ratio.



With use of string, duck tape and a marker to mark the string before the rollback and knowing the dia of the drive shaft you can do this calc yourself.



Otherwise you gotta have someone laying under the pickup whilst you roll it.

 

[WestTN]

First, try looking for a metal tag hanging from one of the bolts holding the cover on. The available ratios in 2001 were 3. 55 and 4. 10. If you have it there will be LS after the number signifying limited slip.

 

[LKuilder]

The easiest way would be just to check one of the few places on the truck that the ratio would be marked. This is only if the previous owner has not changed the gearing from its original ratio. It should either be stamped into the cover on the rear end or on a tag attached to one of the cover bolts. Yours being an 01 should also have a tag under the hood on the bottom side of the hood itself listing all of the options and packages that the truck had from the factory including the factory gear ratio. Hope this helps.

 

[cArNiVaLwOrKeR]

How much would it cost to go from 4:10 to 3:54's ?



JoeLee

 

[BDaugherty]

4. 10, 3. 73, 3. 54

I was unaware that the 3. 73 was available before '03 from the factory.

 

[Crash&Burn]

My 99 with 3. 54 and 245/75/16 tires shows 68mph at 2000 rpm

 

[cArNiVaLwOrKeR]

Is the Sweet spot for mileage @ 1950RPM's ?

Regardless of the gearing...



JoeLee

 

[Shelby Griggs]

It will be 3. 55 or 4. 10 if still stock.



I find the sweet spot for my 2001 is around 1600 RPM, that is about where the TQ curve levels off, and puts me in the 60 MPH range with the 3. 55 gears.



I can literly get 10-25% better milage at 60 MPH rather than 70 MPH depending on winds, this has been checked for over 200,000 miles, therefore I drive between 58-62 MPH about 90% of the time.



SHG

 

[cArNiVaLwOrKeR]

how do you maintain from getting Ran-Down? thats a little slow... I'd drive that slow, but wouldnt want people getting MAD @ me...





JoeLee

 

[HAnderson]

Joe just buy my comp rear end with 3. 55 Howard

 

[cArNiVaLwOrKeR]

Howard, I havent forgot about you, Please let me just make it by Christmas, I promise...



JoeLee

 

[Shelby Griggs]

how do you maintain from getting Ran-Down? thats a little slow... I'd drive that slow, but wouldnt want people getting MAD @ me...





JoeLee

Well in Oregon, 55 MPH is still the limit on ALL but rural interstates, CA has 55 MPH for big trucks, so I just run in the slow lane with the trucks. Sure some folks proably don't like it, you are free to pass anytime it is safe to do so. If I am on a single lane with higher posted speeds AND am holding traffic up, I either pull over OR drive the posted limit in those cases. It doesn't really matter what the limit is posted, I still find folks wanting to go faster, usually be a considerable margin!



SHG