Engine/Transmission (1998.5 - 2002) 3.54's or 3.55's ?

[Pit Bull]

I noticed that most members showed as 3. 54's, but my 2002 owners manual show's 3. 55's. Did Dodge change the rearends from 3. 54' to 3. 55's in 2002. My 2000 service manual does not indicate either way and Fritz's web site does not specify?

 

[BV]

3.5x

Another great debate that no one has the factory answer to. I do know that my 99 came with 3. 55 listed on the build sheet and I'm pretty sure that someone actually counted the ring & pinion gears and did the math to find it was closer to 3. 55 than it was to 3. 54

 

[MikeR]

Dana's designation is officially a 3. 54 in their books, and also a local member (boeing machinist) was fed up and counted the teeth when he had the diff cover off his truck... same 3. 54



DC has made 3. 55 in their corporate axles for years and I think they're just getting lazy in their printing dept.

 

[John]

Originally posted by MikeR

... a local member (boeing machinist) was fed up and counted the teeth when he had the diff cover off his truck... same 3. 54

Geez, who'd be that anal?







Actually, it's 3. 5384615:1 ( )



(46 ring gear teeth, 13 pinion gear teeth... Dana 70)

 

[Pit Bull]

Thanks guys this information might win me a beer some day Based on the responses I will leave my sig. 3. 54, even though my build sheet also states 3. 55.

 

[JR2]

I am going to change my sig to 3. 545

 

[LSMITH]

Has anyone counted the teeth in the front diff? Usually it will be just slightly higher than the rear to prevent a bind. If the rear is 3. 54 the front may well be a 3. 53. Not that it is important or would make any difference.



Stickers on my 99 call out 3. 5 gears and that is all.

 

[andrewkoperdak]

That guy that counted the teeth could have saved himself alot of trouble. It is posted on the differential cover. At least on mine it is.

Pit Bull - lite beer of the good stuff?

Andy

 

[slo-ryde]

There's a metal tag on my rear axle that says 3. 54 so that's what I'm assuming it is...

 

[Pit Bull]

I just changed my sig. to 3. 5 LSD

 

[WadePatton]

I've seen it both ways in DC speak for the same vehicle. It's a hair that I ain't worried about splittin'.



But if I was going to split it, I'd put her on jack stands and do some precise measurement of the actual rotational values--which should vary with wear. Too bad I don't have a front diff to worry about.



Maybe when I get the shop done and run out of other things to do.

 

[John]

no kidding!

Originally posted by AKoperdak

That guy that counted the teeth could have saved himself alot of trouble.

I'm the one MikeR was referring to...



the one that counted the teeth.



I realized then (summer of '98) that there was a tag stating the pertinent information. HOWEVER, being the doubting Thomas that I am, I decided to double check as I was in there anyway changing out my diff. cover and gear oil (I had one of the first Mag-Hytec rear diff. covers... imagine that )



BTW, that was looong before this BB or even the CDW BB was started (of which I was onboard from the very first day)

 

[rujpn2]

ring gear size

Just a thought, but John posted it is 3. 54 for the Dana 70. My 2002 has a Dana 80, code in the glove compartment states Dana M80 (at least that is what I am guessing). The Dana 70 is a 10. 5" ring gear and a Dana 80 is an 11. 25" ring gear. There has to be a few more teeth on the Dana 80 in order to be 0. 75" larger in diameter. My question is, would that be the difference as to why some say 3. 54 and some say 3. 55 on their respective build sheets?

 

[Diesel Freak]

John, I think you would doubt the value of pi to 10 digits.