Engine/Transmission (1998.5 - 2002) axle gear swap

[Jason Griebel]

I've been wanting to change gears for sometime, but lately been towing more and heavier. I have 3. 54 now and want 4. 10's. I also want to up my tire size. my truck stock had 245 want to go with 285, 295,or 315. If my calculations are correct with 4. 10 and 285 speed will be 4. 36 mph slower, 295 - 3. 32, and 315 - 1. 30.



Questions:

1. what tires are anyone using to tow with

2. how do they hold up

3. what size



Gear swap from what I've read if you go from 3. 54 to 4. 10 you need to change carrier, but I found a ring and pinion set that the ring says it's thick to be able to use on the 3. 54 carrier. Has anyone ever seen this or used one? or is there anyone who wants 3. 54 for 4. 10? As far as I can tell dana 60 up front dana 80 rear with limited slip. Looking forward to see what is working for everyone else.



Thanks

 

[JLandry]

Jason,



I had the axle ratio in my truck changed from 3. 54 to 4. 10 by Randy's Ring and Pinon in Everett, WA. We used Dana gears and it did not require a carrier swap. When they opened up the axle they found the limited slip clutch plates were worn out so I those replaced and new bearings installed also.



My truck has Michelin LT265/75R 16E LTX A/S tires which, is what it came with from the factory. They're great for high fuel economy and towing, but since my truck is only 2WD, they may not have an aggressive enough tread for 4WD use.



You'll definitely appreciate switching to 4:10 for towing... it was one of the best upgrades I did to my truck, and I hardly noticed a decrease in fuel economy.



John L.

 

[HBarlow]

I have no experience with larger tires but have seen members who have exhanged their OEM tires for larger sizes and accepted LRD tires instead of the OEM LRE who reported squirm under heavy towing loads. What I'm suggesting is don't downgrade to softer LRD sidewalls or you'll likely regret it. LRD tires, size for size, are not rated to carry as much weight and will be slightly less stable.

 

[n7gxz]

I've been running Michelin LTX AT/2 in size LT285/75R16/E and I have been very happy with them.



I think your calculations are off a bit. Using the LTX AT/2 here is what I come up with.



Size Rev Per Mile Diameter Engine RPM 3. 54 OD Engine RPM 4. 10 OD Speed

LT245/75R16/E 683 30. 47 1813. 365 2100. 225 66. 17531495

LT265/75R16/E 657 31. 65 1744. 335 2020. 275 68. 79412498

LT285/75R16/E 634 32. 83 1683. 27 1949. 55 71. 2898109

 

[Silver_Ram]

I swapped to the 4. 10's when the truck had about 25,000 miles on it.



I run a 315 BFG AT tire on an 8. 5" wheel and the truck runs at 2100 rpm's @ 65 mph in 6th gear (speedo is corrected with a DRB). The truck will take off in third gear, but I only tried a couple of times. It's great for towing my 5th wheel, utility trailers or a dump trailer. With 5th wheels or goosenecks you own or tow, the trailer ride height can also dictate how tall a tire you can run. If you have a low riding trailer, 315's may not work so well.



The tires have been rotated every 5,000 miles and judging from wear, I will get about 65,000 miles out of them.

 

[Jason Griebel]

Thanks for the replys so far I don't see anyone who regretted swapping from 3. 54 to 4. 10

 

[Bob Cochran]

I have not made the swap already have 4. 10 rear. What people have said I have read about love 4. 10's for towing. Absolutely hate them when not towing. I tow a lot so I don't care about the truck when not towing so much so am happy with the 4. 10's. In the final analysis it depends if you tow a lot or not; like a full timer will love them and a person who only tows occasionally not so much.

 

[DACoffman]

I want to put 3. 73 gears in mine. Has anyone tried this?

 

[Jason Griebel]

I trying to identify my rear axle I'm about 99% sure it's a dana 80, but the little tag on the axle that tells what it is is gone. I looked on the tubes and around the casting for the six digit # with no luck. Is there any other easy way to tell what axle I have with out taking off the cover.

 

[PVanderlugt]

I trying to identify my rear axle I'm about 99% sure it's a dana 80, but the little tag on the axle that tells what it is is gone. I looked on the tubes and around the casting for the six digit # with no luck. Is there any other easy way to tell what axle I have with out taking off the cover.

The only ones that got a (modified) dana 70 were the 2500 Auto's, the rest got Dana 80's so yes, yours with a nv4500 is a Dana 80

 

[Silver_Ram]

DACoffman - For all around purposes, the 3. 73 would have been better for me. I was trying to keep the warranty intact. Most of the 3rd Gen trucks are running 3. 73 & seem to do just fine.



Now I may be wrong, but I was under the impression that the 2500 trucks with the automatic or 5 speed manual transmission's came with the Dana 70. The only 2500 that is different is the HO with the 6 speed manual - they got the hybrid Dana 80. There was a 01 Dodge 2500 with a 5 speed in the shop today and the rear axle was a Dana 70. Who knows Dodge has mixed and matched parts on trucks in the past, which can throw people for a loop.

 

[Jason Griebel]

What's the difference between a dana 80 and a dana 80 hybrid? Is there any visible difference?

 

[Silver_Ram]

The axle diameter is smaller in the Hybrid axle. I don't know how much.

 

[Jason Griebel]

For those who have swapped gears. Do you think it would be easier or better to swap the entire axle or just swap gears and carrier?



If swap gears how hard is it to get the carrier out of the front?

How hard is it to reshim?

I guess how what's involved in doing it either way?

 

[Jason Griebel]

Have any of you guys tried gear swapping yourself? How hard? Any trick or something special to look for?

 

[macdaddy]

Jason... .



My 99 had the axel model and ratio under the hood. Look up as the hood is lifted. It may be covered in dirt.



Mac

 

[Jason Griebel]

Mac,

I did find that sticker and I do have a dana 80 hybrid. I found a guy with basicly an identical truck with 4. 10 and would like to swap just would like to know what would be the best way to swap entire axle or just gears. Would like some insight.

Thanks

 

[Silver_Ram]

It sounds like you may want to find a drivetrain shop to swap things out for you. If both trucks have some miles on them - replacing the inside bearings would be a good idea.

 

[macdaddy]

Jase



Mine had the same model 80. I would definitely do a gear swap rather than a whole axel swap. You might wind up with some launch shudder, and or vibration issues.



Mac

 

[KKlingbeil]

A gear swap seems like it should be easier, but after replacing ring and pinion and limited slip clutch packs, I would disagree. This was my first rear end rebuild, but was also working with someone that had done a lot of them. If you have everything out, then you might as well put in new pinion bearings and carrier bearings. Beings your putting in your "new" carrier in a different housing, the shimming from the old housing means very little in your housing. If your going to do the gear swap yourself, I would buy an extra set of new bearins and hone them out so they slid on the pinion and carrier easily. The shims are behind the bearings and the bearings are pressed on, making it a pain in the rear when you are trying to get everything set right. Good luck!