2nd Gen Non-Engine/Transmission srw to dually

[justatruck]

I was thinking about pulling my bed off and making my truck a dually. What do I need for the rear end? I know the fronts have the spacer, but I'll probably just leave the front the way it is... a 3/4t. What about the rear... I just need dually wheels right? Sorry I know this has been covered before. re: '02 3/4t HO (Dana 80 w/ disks). Thanks -justatruck.

 

[Joseph Donnelly]

If you just bolt on dually wheels in place of a single wheel you have moved the centerline of weight carrying outboard about 1". This puts more leverage on the bearings and actually decreases weight capacity. Those who use the 2" or so thick spacer have moved the weight carrying point outboard even farther and have really detracted from capacity. The point with one tire is the center of the tire. With two (dually), it is the center point between the tires. Of course, with a dually you get up on only one tire occasionally, and that can momentarily increase leverage a lot.



Add to the above the likelihood that the diff had only 6200-6500 lb capacity if a single rear whel truck. Adding tires with more capacity doesn't do it. There are more bent axle housings out there than you might think, from overloading, etc.

 

[MAX A/C]

"The point with one tire is the center of the tire. "



This is true with 0" offset wheels only, correct? A dually wheel, when used on the front axle, is putting a higher load on the wheel bearings (or at least the mounting studs/surface) due to the leveraging effect of the huge offset, right?



Just asking, as I've always wondered this point.

Scott

 

[justatruck]

What I was trying to confirm is that the axles are the same width and have the same hub regardless of srw or drw right?

 

[bighammer]

I'm not certain, but I thought the 3500 axle is narrower. A look in the service manual might tell you.

 

[RustyJC]

Originally posted by MAX A/C

A dually wheel, when used on the front axle, is putting a higher load on the wheel bearings (or at least the mounting studs/surface) due to the leveraging effect of the huge offset, right?

The offset of the wheel is compensated for by the offset of the spacer. That's why the spacer is there - to put the centerline of the tire in the appropriate plane relative to the wheel bearing locations.



Rusty

 

[Chris Bethurum]

I believe all manufacturer's dually rears are on the order of 4-8 inches narrower. I too am interested in how a person might convert to a dually for periodic heavy towing with a vehicle that is also used unloaded most of the time.



I am curious if the wheel bearings are same in the SRW and DRW Dana 80s. Anyone know?



I would think someone could use some custom offset dually wheels to be used on the wider SRW rear and throw on some kind of fender. The front wheels could remain the same. Anyone know if this could be made to clear the brakes and keep the same tire track width if not a little narrower than a standard duallys rear wheels?

 

[No Neck]

I know for a fact that the wheel studs are longer on a Dually by about 3/4 of an inch.

 

[Philip]

I believe all manufacturer's dually rears are on the order of 4-8 inches narrower

The single tire SRW is the narrowest axle used.

The Cab and Chassis axle is the next in width.

The Dually P/U is the widest.



If you try to put duals on a single tire width axle. I bet you will find the axle is at least 3/4" to narrow (per side) for the inner dual to fit. Then to allow tire side movement you need at least 1" more per side to be safe.



If you think of spacers to cover the problem. Remember if that truck spits a set of duals. If it ends up in front of a jury. This mod will loose in a court of law most likely.

 

[Joseph Donnelly]

weight capacity of a diff is matched by tire capacity. So, your SRW diff is rated about what two tires give it. Four tires won't double the strength of the axle housing.

 

[Chris Bethurum]

Thanks for the responses



I looked at an F350 DRW and SRW and could have sworn from about a 5 minute eyeball comparison that the srw was wider from axle flange to axle flange. Oh well. So it sound like a spacer needs to be put in there.



Again, are the bearing different/higher capacity in a DRW vs SRW Dodge with a Dana 80? Housing/axle tube ratings were added to the mix. Might as well throw that into the question. Stronger axle tubes on the DRW Dana 80?



CHris

 

[Shovelhead]

Check out www.arrowcraft.com

 

[Wiredawg]

I traded....

Fellow rammers:



I too considered converting my 00 2500 4X4 QC LB into a dually, but came up with too much cost/work for the result.



I traded my '00 w/ 56K miles for a new 02, stripped my 00 of all the added on goodies (including 4" exhaust; injectors, gauges, exhust brake, heavy duty rear bumper, grill guard, headache rack, roll top cover, tool box, nerf bars, 5th wheel hitch and TST Power max) and got the 02 end of year 0 interest for 60 months.



Did is say this was less work



Wiredawg

 

[Rob Thomas]

From what I understand, the the hub assembly is the only thing different from the SRW to DRW on the Dana 80's. Which was backed up from Fritz's site... . "Dana 80 2500 axles and 3500 axles are identical except for the outer wheel spindle and hub assembly. "



Sounds like a simple swap to me, however I have never done it, yet.



Rob

 

[Chris Bethurum]

Thanks for the info, it may be worth looking further into. At this point I won't plan on loading anything past it's original rating, but the added insurance and handling with a dually may be worth it at the limit..... plus it's a gear head project as long as it's not too expensive, whatever that is.

 

[justatruck]

Thanks for the replys everyone. It looks like I may be going ahead and trying this in the near future. I'm planning on priceing the hub assymblies and rotors (for the longer studs) tommarow. It looks like I'll end up with a wider than usual dually, but that shouldn't be a problem since I plan on a flatbed. Thanks again.

 

[LandShark]

Check out Ricka Mfg. . I've used this setup for about 50,000 miles of 3500# camper hauling.