I’m throwing around the idea of swapping 4:10s for 3:73s to grab lower rpms and higher mpgs. Anyone here ever done it? Is it something that could be done myself or need to be taken to a shop? At that ratio difference is a new carrier necessary? Easiest way seems to swap entire front and rear end but it’s hard to find someone near me with what I want lol. 

You can run 35-inch tires with 4.10 easy. I've got a local gent that insisted on keeping his 37-inch tires so he swap out front and rear axles 3.55 gears for 4.10 and now has good power once again for that large of a tire. Cost him about $4,000 to be swapped out locally. 

I got quoted $3,000 for 3.55 to 3.73 yukon gears

On 3/18/2018 at 2:31 PM, AH64ID said:

A 315 is going to be about 130% the weight for a 4% reduction in rpm. 

 

Why I've never jumped in the over sized tire game. 

38 minutes ago, Mopar1973Man said:

 

Why I've never jumped in the over sized tire game. 

 

They do have a place and a purpose, but if they are just for looks then I'm not interested. 

 

I like the 255/80R17 for the added axle clearance in deep snow. It's amazing what just a little bit will do to help. 

14 minutes ago, AH64ID said:

They do have a place and a purpose, but if they are just for looks then I'm not interested.

 

Absolutely. Like out here the ranchers commonly devote one truck for wide tires so they can float across muddy fields for feeding cattle. 

 

Like how I see tires. If I was to step off into the snow with normal boots on I would sink to the bottom. If I put on snow shoes I can walk on top. So that being said wider tires will allow a vehicle to float on top of a surface be it mud or snow. Narrow tires will sink in and bite the road way better. Since I know my front axle weight is 4,440 pounds typically that is 2,220 pound on each tire. So if I've got narrow tires on there is more weight per square inch pressing down to the road way. Where a wider tire will have less pounds per square inch pressing down allowing the vehicle to float on a surface better. 

 

So yes I understand the purpose and reason of wider tires. But 90% of the truck on the highway I look at every day never see a muddy field or even leave the pavement. Nothing more than "Pavement Princess". Like where I live most of the truck with wide tire that roll into town are got mud and slop to the driver window. But these are true work trucks.

5 hours ago, Mopar1973Man said:

You can run 35-inch tires with 4.10 easy. I've got a local gent that insisted on keeping his 37-inch tires so he swap out front and rear axles 3.55 gears for 4.10 and now has good power once again for that large of a tire. Cost him about $4,000 to be swapped out locally. 

Not worth the price. Will 35s keep mpg the same or lower it? 

I’m not terribly worried about rpms as much as mpg and noise. I’m all good w Th running 60mph for mpg but I need to be able to quiet the darn truck lol. It’s mainly engine noise. Exhaust has a very slight drone nothing crazy loud. Anyone ever tried to quiet down there motors? 

Best way to quiet down a 2nd gen is to get a 3rd gen 

 

The VP trucks are the noisiest Cummins ever put in a Dodge. 

8 minutes ago, AH64ID said:

Best way to quiet down a 2nd gen is to get a 3rd gen 

 

The VP trucks are the noisiest Cummins ever put in a Dodge. 

Not happening lol. I friggin love this truck. Just needs to be a lil quieter I’d possible... lol

25 minutes ago, Marcus2000monster said:

Anyone ever tried to quiet down there motors? 

I hear earplugs or a loud stereo work wonders.  

29 minutes ago, SilverMoose said:

I hear earplugs or a loud stereo work wonders.  

Ahem there goes my already shot ears. 

On 3/19/2018 at 7:19 PM, AH64ID said:

Best way to quiet down a 2nd gen is to get a 3rd gen 

 

The VP trucks are the noisiest Cummins ever put in a Dodge. 

Ha ha funny, but in all reality I think in distant or maybe not so distant future I'll get 4th gen and skip the 3rd all together, kinda what I did with pager/blackberry era. The only 3rd gen that I may consider is an 07 g56. Not sure why or when but just thinking out loud. 

On 3/18/2018 at 12:58 PM, AH64ID said:

It will take tens of thousands of miles, or more, to offset the cost for just a mpg gain even if you do the work yourself. If you were to go from 14 to 16 mpg the CPM would be reduced by less the 0.03/mile at 3.00/gal. If you did the gear swap for $1000 it would take 33K miles to cover the cost. In my research for swapping from 3.73 to 4.10, for towing purposes, it would cost closer to $3K to do the swap and that would take 100K miles to recoup the cost. Going from 16 to 18 mpg would would be a 0.02/mile savings and thus take 150% longer to pay off. 

 

I think a 2mpg gain is unrealistically high... basically it's not going to save you any money unless you plan to put 250K more miles on the truck. 

 

If you've never setup gears before, which I gather you haven't, I wouldn't do it yourself. 

 

Go with a taller and skinnier tire on your next set, it will reduce rpms without a large increase in rolling resistance/weight. 

 

A 255/85R16 would be a 5% reduction in rpms over a 265/75R16, which is just over 1/2 of the change you would get with a gear swap. 

I dunno about that. I regeared my whole truck for under$200. I haven't gone for new bearings yet but when I junk yarded the rear gear I took all the bearings too, and the front gears I bought off eBay came with bearings. I picked forthe best ones, greased em up and let her rip. Now for a front driveshaft and I have to learn how to operate this cad thingy and I'll be ready for winter. Me thinks winter will be a rough one this year.

Most folks aren't able to setup gears themselves, or wanting to use junk yard gears. While it does reduce the cost it's not the most common method. 

Yeah I know. But a lot of folks also don't know it can be done that way. From what I've seen unless an axle has been completely neglected there's no reason the r&p can't be reused. I found separating the bearings from the pinion and the carrier to be the most frustrating part of the job. This weekend I made a homemade separator otherwise I would've been unable to complete the job. I guess what I'm saying is some research and a little outside the box thinking can save a big pile of cash.