rear end swap

bucky wrote:
I don't see where you state what ratio you have now, so I'll go with a 3.55 as it was the standard on trucks from Dodge of that era. I would do the swap, but probably with new ring and pinion hardware and bearings etc. Used parts are crazy high around here at least, so buying a whole rear may not save much if anything. Also, you will never want to go back to the 3.55s. I have swapped ratios several times on my gassers and find that my towing mileage increases without much effect on empty mileage. The 4.10s put my trucks into the power band for pulling hills better loaded as well as the 50/55 mph zones in 3rd with the converter locked, and allowed OD loaded on the interstates.

Ditto this.

I run a '02 4.7 1500 and went from a 3.55 to a 4.10 and this is exactly what it did for me. With the 3.55 the transmission was constantly up/down shifting. The 4.10 allowed it to stay in a particular gear within the power band. My engine/tranny combo is probably quite different from yours but it allowed me to tow for 8 years with this truck.....

X2 on the gear swap! the 5.9L loves that ratio when towing. I had a 97 Dodge conv. van with the 5.9L and 3.55. when I swapped to a 3.90 it was a night and day difference! you will love the lower ratio (numerically higher).

I too would do the gear swap. much better than getting something unknown, that will more than likely need a rebuild anyway, usually the bearing are noisy with higher mileage.

Good luck!

What he says ^^^^^^^ :)

I don't see where you state what ratio you have now, so I'll go with a 3.55 as it was the standard on trucks from Dodge of that era. I would do the swap, but probably with new ring and pinion hardware and bearings etc. Used parts are crazy high around here at least, so buying a whole rear may not save much if anything. Also, you will never want to go back to the 3.55s. I have swapped ratios several times on my gassers and find that my towing mileage increases without much effect on empty mileage. The 4.10s put my trucks into the power band for pulling hills better loaded as well as the 50/55 mph zones in 3rd with the converter locked, and allowed OD loaded on the interstates.

The only issue that I see is that any rear end you get from a wrecking yard will be a gamble and potentially Abused and in need of a rebuild itself.

If it were me, I'd take the gear swap route and have the entire rear end gone through. Nothing likes broke used part to ruin a trip.

JMHO. But either option is very viable.

Thanks!

Jeremiahrq

Nothing wrong with wanting to exchange the rear end. When you find one at a salvage yard, see if they'll let you pull the cover off of it while you're there so you can see if there's any busted teeth or pieces of metal inside before you leave. If not, at least pull the cover at home before you get started on the installation.

Bill

I am not trying to increase my speed, I am trying to get into the powerband of my truck at a lower speed. Currently it pulles the trailer great at just over 70mph, I want to run the same rpm at 60mph. Fuel mileage is a non issue. I only drove the truck 1500 miles last year, and get 7mpg towing, it will not get much worse, I rarly run empty and don't mind buying the gas when I have to. I pull the RV to go have fun, not to save money. I just hate it when I hit an incline and lose speed till I can downshift to third, only to have to shift right back to 4th when my rpm and speed get back up.

All that being said, swapping the rear end and getting parts from the salvage yard sounds like fun to me, so why not? If I don't like it, I will just put the old rear end back end and sell the one I bought at the salvage yard.

First of all, if your doing this to give you more pulling power, you'll be disappointed.

I went from 373 to 456 gears and only increased my speed up the same 6% grade towing the same 5th wheel by 10 MPH. I would have rather spent the $1300 on fuel.

Plus when my truck wasn't towing it got worse gas mileage unless I stayed at 55MPH. It went from 10MPG to 8MPG empty with the new gears if I tried to stay with the flow of traffic.

Most wrecking yards have interchange manuals that can tell you this info.

I personally think your doing it the correct way. I like the complete rear end deal rather than the gear swap. This way if you don't like it you can go back to the old ratio.

Could you cruise an auto salvage yard for same truck with the rear end installed and use? The rear end not the truck.