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Discussion Starter #1
Hey,

So I'm looking for a step van to convert into a camper and need some advice. I've been looking for a 4BT for obvious reasons, but am having trouble finding one exactly how I want - barn doors at the back, 18ft cargo area, 7' tall inside, highway gears, max 10,000 GVW, 16" wheels...

I've found one locally on craigslist which ticks nearly all the boxes (except the wheels are 19.5" $$$$, not sure about the gearing, and it's a 3.9 ISB rather than a 4BT) and am considering it. It's a Workhorse base, with Freightliner body I think, Allison auto trans and 100k miles.

I would really appreciate you knowledgeable people's advice on the common rail ISB vs. the 4BT. I've not been able to find much info online but the little I've found hasn't really reassured me... Computer/electronic stuff that'll be more complicated/cost more to fix when it goes wrong, parts harder to source and more expensive, and generally lower build quality compared to the older all mechanical 4BT.

Any input appreciated!
 

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19.5 wheels are a bad thing?

The RGT commonrail engines are pretty nice. Why would you feel they are hard to get parts for or problematic?
 

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Discussion Starter #3
Not a bad thing necessarily, but the tires are crazy expensive to replace compared to 16"s ($300 each x6) and I'm on a budget...

And I know very little about the common rail engines, hence this thread, but from the googling I've done over the past couple of days the general consensus seemed to be the 170 ISBs were built less well than the 4BTs and the added electronics could be more prone to failure and would make repairs more difficult/expensive.

But I'm far from being an expert and so I'm here to get people's opinions. I'm glad you feel they're OK engines anyway, that van is tempting me for sure.
 

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Don't know that I would be afraid of the ISB engine. Virtually every Cummins except for a few commercial models are HPCR engines. Also it's a bit quieter than the 8 valve engines with its rear gear train.If the transmission is the Allison 1000 that would be a plus since it has a OD gear and designed to handle your load requirements and quite a bit more. 19.5 tires are normal on commercial vehicles and you find them on campers as well. From what I've seen of tire prices lately they aren't that much more expensive. Just don't have as much of a selection to choose from. If you want to dress it up there are 19.5 wheel covers and aluminum wheels. As for gearing you'll have to check what it has and see what rpm range it makes the engine run. If you'll be driving a lot of interstate miles then you may need something higher. 100,000 miles is nothing on a Cummins if it has been properly maintained. Just barely broken in.
 

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Discussion Starter #5
Alright well I'm waiting to hear back from the seller to see what tranny it is exactly and the gear ratio. Will be using it for quite a bit of highway driving so hopefully it's not geared too low. Thanks for the input so far and for putting my mind at rest somewhat. Any other opinions and advice welcome...
 

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You should prefer 19.5's over 16's. Last 2x longer drive/handle weight better.

I would like to see all the "electronics" and "computers" that go bad on the newer cummins engines. I think a lot of it is the old guys not being able to fix/adjust things with a wrench instead of a computer and complaining.

Throw the word budget out the window, your stepping into medium duty vehicle territory. And why do you want a 10K gvw max? I don't understand why that matters, your looking to purchase a medium duty vehicle... You don't have to worry about gvw until you get over 26,000.
 

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Discussion Starter #7
I was under the impression that <10,000 would mean cheaper registration and insurance (yes, budget again :D) and less hassle with parking regulations.
 

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My 4BT came in a Grumman stepvan, a Chevy P-30, the longer one. It had a TH475HD in it and another one sitting on the floor in back! The trans that was in it in use was the 3rd TH475HD for this van! The tire size and gear ratios and auto trans should be real similar to your rig mentioned, if you get it.

My best buddy and I drove back home about 100 miles in it, up California Hiway 5 and Hiway 99. These are major State Hiway routes out here both for transport trucks and locals. In the last part of the trip we were driving through the mountains in Nor-Cal.

Overall the van did just fine! I was in no hurry and can develop an attitude about folks that try to push me and rush me on the hiway, making my feelings very obvious to them visually and otherwise. We had no trouble cruising 60-65 and the truck pulled the hills easily. Only real problem was a bumper to bumper, barely crawling traffic jam somewheres, and on a hill on a toasty warm summer day [!!!!] when she wanted to overheat. It got dangerously close but managed to survive.

I personally would be real happy with a stock stepvan drivetrain for an RV, again not in any big hurry. The bigger P-30 length van might equate to a shorter P-20 length with some RV parts installed so it seems it would be pretty similar. When considering suitability one has to figure that these stepvans were commonly used in stock trim as fully loaded for route vans over all types of roads from city strets to major interstates - they did just fine and still do!
 

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Pseudo,
I'm in the middle of building out a step van RV right now. great minds think alike. Where are you in PA? You're more than welcome to check out my project any time. I'm in the Philadelphia area for another month. Mine's a 15' cargo area-sized Freightliner MT 35.
Stephen
 

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Discussion Starter #11
Pseudo,
I'm in the middle of building out a step van RV right now. great minds think alike. Where are you in PA? You're more than welcome to check out my project any time. I'm in the Philadelphia area for another month. Mine's a 15' cargo area-sized Freightliner MT 35.
Stephen
I'm in West Chester. That sounds great, would def be interested in checking out your conversion. Will send you a PM with my contact details.
 
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