Help me pick my first 1st Gen (Cummins) truck!
- Thread starter LJinLA
- Start date
Metcalf
Expedition Leader
With your difficulty finding a truck and what you have mentioned about modifications I would think HARD about the diesel. Being a dually truck it might also have 4.10 gears too, well worth checking into.
For larger tires starting with a dually rear bed minus the fender flares would save a LOT of body work. Depending on the height of the vehicle and tire size you may have to do a little trimming/moving on the inner tub. Basically the outside corners of the wheel tub may need a little work to clear a bigger tire. The wheel opening on the dually bed is LARGE, way larger than what I did. 37s may looks small. You might be able to make the opening look a touch smaller. Maybe some universal fender edge flare or something. It is a nice big clean opening.
In the front I would look REALLY hard at the Trailer Products front fenders. I think they have a 'taller' opening than stock that would go with the dually opening very well. You would have to trim out the inner fender and fabricate some replacement shielding in some areas.
If I was going to build a 1st gen Cummins with big tires again that is what I would do.
I think those are 35s. They looks SMALL in that huge opening. I would love to try 40s with a little sheetmetal work to the inner tub. I think in the front however you would have to push the axle forward slightly run anything larger than a 38-39" tire even with sectioning the fenders like I did.
Here is a little better picture of the dually wheel opening. You can see the inner wheel tub. I would paint the inner stuff black to hide it a bit.
These are the Trailer Products front fenders. The opening is large and tall. I think it would match the factory dually opening really well.
Its almost a shame you can't lower the truck a bit with the REALLY large openings. The 1st gen Cummins already suffers from a lack of uptravel in the front. Maybe dropping the body would be possible or something. I never looked into it much.
Just a few ideas.
Post some pics of the truck your considering!
Metcalf
Expedition Leader
I was also going to mention about tires and wheels....
I think running some custom wheels is possible to make the dually axles work just fine. Even running different backspacing front and rear would be possible.
The front axle is pretty easy to convert back to SRW with some new bearing hubs.
I am not super sure about the rear axle. A cheap GM 14-bolt is about the perfect match to the factory Dodge SRW front, I think even better than the factory D70 rear axle which in my opinion is a little too narrow.
I think running some custom wheels is possible to make the dually axles work just fine. Even running different backspacing front and rear would be possible.
The front axle is pretty easy to convert back to SRW with some new bearing hubs.
I am not super sure about the rear axle. A cheap GM 14-bolt is about the perfect match to the factory Dodge SRW front, I think even better than the factory D70 rear axle which in my opinion is a little too narrow.
As a matter of fact, that's precisely the feedback I've got in another forum in this regard, that running only the outer dual wheel will exert a lot of force on the lugs, which is fine provided the truck's bed is driven unloaded with this setting. The load of a heavy camper would overstress the lugs and wheels. It was suggested that wheels with proper backspacing would alleviate the stress factor some.
I wasn't thinking much in terms of doing any serious offroading, but rather with a view on getting better fuel mileage by removing the inner wheels so as to make the truck lighter/more agile, if this makes any sense.
Thanks Metcalf for the precious feedback and pictures...it's all very helpful. The 4.10 gears likely to come with a dually would for sure be a plus when running large tires.
Actually, I don't have a specific truck that I'm considering at this time. I was just considering the various possibilities to be open to. Being open to the idea of getting a DRW and not restricting myself to SRW trucks only of course betters the chances of finding a suitable W250 manual sooner.
Yep, wheels with proper backspacing seem necessary in order to avoid placing much stress on the rear lugs/wheels when running just the outer wheels on a DRW axle. But it also implies more money to be spent upfront when getting the truck (for proper rear wheels), and then when the time comes to do a conversion to SRW axle....that initial investment will be gone to waste.....
I've read a lot of positive things about the GM 14-bolt as a good prospect for an SRW conversion - much sturdier, appropriate and easier to maintain than the factory D70.
Actually, I don't have a specific truck that I'm considering at this time. I was just considering the various possibilities to be open to. Being open to the idea of getting a DRW and not restricting myself to SRW trucks only of course betters the chances of finding a suitable W250 manual sooner.
Yep, wheels with proper backspacing seem necessary in order to avoid placing much stress on the rear lugs/wheels when running just the outer wheels on a DRW axle. But it also implies more money to be spent upfront when getting the truck (for proper rear wheels), and then when the time comes to do a conversion to SRW axle....that initial investment will be gone to waste.....
I've read a lot of positive things about the GM 14-bolt as a good prospect for an SRW conversion - much sturdier, appropriate and easier to maintain than the factory D70.
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redthies
Renaissance Redneck
I know what you are saying. I have read numerous reports on fuel economy where there is only +/- 1 mpg difference with both duals versus singles (on the same truck). You would need to drives ton of milesat 1 mpg to pay for any damage caused by running a single rear. Unless of course you buy wheels with a different offset. It would also take a lot of miles at 1 mpg to pay off a new set of wheels. This is assuming fuel economy is the main reason you would go single.
Metcalf
Expedition Leader
With the right wheels you might not have to convert to SRW. You could just leave it.
It would be interesting to see how a set of the H1 hummer wheels fit with the 7" backspacing on the dually axles. The front might end up a touch wider than you would like but then again maybe not. You can get the 37" BFG baja hummer tire now. If you could use unmodified steel H1 hummer wheels that might be a really good budget way to get larger tires.
http://www.trailworthyfab.com/Tires/
Anyone have any firm numbers on the DRW axle widths? SRW is about 67.5" in front and 65" on the rear axle.
It would be interesting to see how a set of the H1 hummer wheels fit with the 7" backspacing on the dually axles. The front might end up a touch wider than you would like but then again maybe not. You can get the 37" BFG baja hummer tire now. If you could use unmodified steel H1 hummer wheels that might be a really good budget way to get larger tires.
http://www.trailworthyfab.com/Tires/
Anyone have any firm numbers on the DRW axle widths? SRW is about 67.5" in front and 65" on the rear axle.
rxinhed
Dirt Guy
Yet another solution to your SRW/DRW dilemma was dealt with by Stockton Wheel, and similar businesses, many years ago when they made Super Single wheels. Big rigs have used these for several years, too:
My Chevy had 33x12.5-16.5 tires in front and 255/85-16 tires in rear. I would question that a Dana 70 has less maintenance needs than a 14-bolt GM axle, not understanding the logic there. Running single dually wheels on the rear axle is a last resort thing to me based on the lug issue first, appearance second.
When I was able to drive my 77 Dodge around, I didn't have any driveability issues specifically caused by the duals. My work at the time was earthwork projects. However, my truck was a full-time unit with 4.88 gears...averaged about 3 mpg on the highway. Someone wanted the truck more than I did, and sadly departed with my truck, about $4000 in tools, and all the equipment I had in the service body. Since 1998, I have missed this truck:
My Chevy had 33x12.5-16.5 tires in front and 255/85-16 tires in rear. I would question that a Dana 70 has less maintenance needs than a 14-bolt GM axle, not understanding the logic there. Running single dually wheels on the rear axle is a last resort thing to me based on the lug issue first, appearance second.
When I was able to drive my 77 Dodge around, I didn't have any driveability issues specifically caused by the duals. My work at the time was earthwork projects. However, my truck was a full-time unit with 4.88 gears...averaged about 3 mpg on the highway. Someone wanted the truck more than I did, and sadly departed with my truck, about $4000 in tools, and all the equipment I had in the service body. Since 1998, I have missed this truck:
rxinhed
Dirt Guy
It's a 2WD auto, though very clean. I've passed on a similar deal (truck in very clean condition) just two days ago, the owner wanted $3,800 and it included a shell matching the body of the truck.
This guy wants $4,900 cash. I could have gotten a 1989 2WD auto just a few days ago for $2,300-$2,500, though not as clean as this one, with about 200K miles on it. Very tempting, but I've resolved to wait for an intercooled 4x4 manual, which I feel is what best serves my needs and what I really want. But thanks for posting this deal here, rxinhed, perhaps somebody else reading this thread will be able to go for it.
Well, I've seen that many of the trucks on sale come with tires in poor condition, so replacing four tires is more economical than replacing six, for one. And was also thinking that it would make the truck a bit lighter, more agile. I don't intend to carry a heavy camper or huge loads.......just trying to factor in all pros and cons and seeing what the possibilities/intelligent choices are.... You guys are helping me out a lot in doing it..
This would be really great! ...if feasible. I've looked at those tires and they are indeed economical. Do we know of anybody who is running H1 hummer wheels on their first gens? I'm eager to learn more about this, because it could be an excellent solution for running affordable, strong 37" tires...and if it works as you have envisioned as a cheap and easy DRW-to-SRW "conversion"......it's a great idea indeed!
I don't quite understand the concept of Super Single wheels that you mentioned just by looking at the picture you posted. It seems to me a regular DRW truck with a service body.
I didn't state that a Dana 70 has less maintenance needs than a 14-bolt GM axle......I wrote that a 14-bolt GM is easier to maintain than the factory D70 with in mind the 14-bolt being cheaper to maintain than a D70 when stuff needs to be replaced and also easier to work on than the D70.
I agree that, because of the lug issue and appearance, running single dually wheels on the rear axle should be considered not as a first choice, but in view of the solution proposed by Metcalf, that is, running H1 Hummer wheels with 7" backspacing on DRW axles...it could really be a good solution if viable. That's what I find of great value in these forums, that by asking questions often solutions pop up that weren't thought of before, and this is truly a great forum!
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rxinhed
Dirt Guy
The super single concept is to place a single floatation tire in place of the standard duals. Lots of OTR trucks are now 6-wheeler instead of 10-wheeler using super singles. On the Chevy I had, the front tires and rims are significantly wider than the rear. This does not allow tire rotation between front and rear axles, however. I uploaded additional pictures hoping to describe super singles better.
