2006 Roadtrek 210 tire capacity and dually conversion options

[TWX]

I guess moderators, if you feel this thread has grown beyond an introductory thread, please relocate it, I think that, "Tweaks, Mods & Projects," is probably a better home for it.

 

[TWX]

Getting back to my undercarriage inspection, the previous owners had replaced the leafsprings.

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They said that there was objection to the ride quality as I alluded to.

I found a boot on one of the rear shock absorbers that is rather out of sorts. I'll need to revisit this later:

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The biggest structural stuff I'll need to work on are the brackets that retain the under-body storage drawers. the Roadtrek brackets under the boxes are bolted with four fasteners apiece to extensions that are welded to the frame:

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The steel is not of the same grade as the GM steel and they're corroding:

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I may reach out to Roadtrek to see if they sell any replacements. If not they're not exactly complicated.

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If they aren't available or are too expensive, I may even look at recreating them in aluminum instead of steel. I have a TIG welder and after a lifetime in IT as both a profession and a hobby I have access to aluminum telecom rack parts, the verticals are typically 3" wide. Close enough to these that I can probably make something that'll work if I get some additional aluminum for the vertical and gusset portions. Would need to paint the side facing the steel frame to avoid galvanic corrosion but a potential weight savings might well be worthwhile. Even if I have to use steel though, I don't think it would be especially difficult. If I do make them out of steel I'd probably have them powdercoated.

 

[TWX]

I had a random unexpected opportunity to measure a Chevy Express dually, a model that's '09 or later based on the dash.

inside-to-inside the leafsprings seem to be 45-5/8" apart. This is in contrast to the regular van having them 48". They are still 2-1/2" wide leafsprings, so 48-1/8" on-center, 50 5/8 outside-to-outside. This means that the leafsprings on the dually are 2-3/8 closer together, or each perch would have to move outward 1-3/16" to line up with van leafspring mounting.

Additionally the brake caliper mounts seem to be very close to the springs:

Unfortunately I was not in a position to get an actual measurement. It would be awfully close if there is room, and I'm not sure that there is.

I also measured inside sidewall to inside sidewall on the tires. My picture did no come out especially well, but there's 56-1/2" between inner sidewalls. That's tighter than the van-axle, but still wider than the van leafsprings and body, so if the brakes somehow were to miraculously clear the suspension it might not require spacers at all in order to fit the dually wheels in between the interior body/springs on the Roadtrek 210.

I think if I'm going to bother continuing this little exercise, I'll need to find a junkyard cab and chassis or cutaway that has its axle and frame still attached at the leafsprings but the aftermarket body removed. I need to know the actual clearance between the brakes and the leafsprings.

So to recap:

1. Van/Wagon have wider perch spacing on-center than cab-and-chassis and presumably commercial cutaway to the tune of 2-3/8".
2. Factory spring perches would need to be relocated for this to work at all.
3. Van/Wagon leafspring width might not let this work because the cab-and-chassis brakes might not clear the van/wagon leafspring 53" width.

 

[booster]

I had a random unexpected opportunity to measure a Chevy Express dually, a model that's '09 or later based on the dash.
View attachment 2439009

inside-to-inside the leafsprings seem to be 45-5/8" apart. This is in contrast to the regular van having them 48". They are still 2-1/2" wide leafsprings, so 48-1/8" on-center, 50 5/8 outside-to-outside. This means that the leafsprings on the dually are 2-3/8 closer together, or each perch would have to move outward 1-3/16" to line up with van leafspring mounting.

Additionally the brake caliper mounts seem to be very close to the springs:

View attachment 2439016

Unfortunately I was not in a position to get an actual measurement. It would be awfully close if there is room, and I'm not sure that there is.

I also measured inside sidewall to inside sidewall on the tires. My picture did no come out especially well, but there's 56-1/2" between inner sidewalls. That's tighter than the van-axle, but still wider than the van leafsprings and body, so if the brakes somehow were to miraculously clear the suspension it might not require spacers at all in order to fit the dually wheels in between the interior body/springs on the Roadtrek 210.

I think if I'm going to bother continuing this little exercise, I'll need to find a junkyard cab and chassis or cutaway that has its axle and frame still attached at the leafsprings but the aftermarket body removed. I need to know the actual clearance between the brakes and the leafsprings.

So to recap:

1. Van/Wagon have wider perch spacing on-center than cab-and-chassis and presumably commercial cutaway to the tune of 2-3/8".
2. Factory spring perches would need to be relocated for this to work at all.
3. Van/Wagon leafspring width might not let this work because the cab-and-chassis brakes might not clear the van/wagon leafspring 53" width.

You should be able to find a cutaway van without a box at a Chevy dealer that sells the light trucks. The often aren't on the main lot because the public isn't interested in them.

 

[TWX]

You should be able to find a cutaway van without a box at a Chevy dealer that sells the light trucks. The often aren't on the main lot because the public isn't interested in them.

Will have to do that, there's such a dealer a mile and a half from my house and they have had commercial vehicles (they still have signage up for servicing Isuzu commercial trucks) on the lot.

 

[booster]

Here is a site that lists the 3500 with 139" wheelbase as 42 frame width.

https://www.countryworktrucks.com/details-2025-chevrolet-express_commercial_cutaway-3500_van_139_-new-1gb0grf71s1103305.html

 

[TWX]

Here is a site that lists the 3500 with 139" wheelbase as 42 frame width.

https://www.countryworktrucks.com/details-2025-chevrolet-express_commercial_cutaway-3500_van_139_-new-1gb0grf71s1103305.html

I'd started with this document:

https://www.gmupfitter.com/wp-content/uploads/2021/05/2006_LD_GHFullSizeVans.pdf

It does show differences between regular-bodied vans/wagons and cab&chassis and commercial cutaways. Unfortunately it doesn't show leafspring positions, just frames and tires.

 

[booster]

I can't be certain, but I think the springs are always in line with the frame rails on trucks.

 

[TWX]

I can't be certain, but I think the springs are always in line with the frame rails on trucks.

That was a good call.

I hadn't looked up the GMT-900 truck platform (2006-2013) even though I'd downloaded the upfitter's guide for it (specifically model year 2011). That upfitter's guide specifies a dimension for frame plus leafspring from the midpoint of the truck. For a conventional pickup with bed this is 26.5", which would thus be 53" width across the leafsprings, outside to outside.

Dually trucks appear to have the same frame, same spring perch width. That should mean that their axles are similarly wide. The dually 1385.8mm clearance inside-sidewall to inside-sidewall is 54.56". Tight to the leafspring for sure but should fit.

I thought that GMT-900 had switched wheel bolt patterns to 8 on 180mm rather than 8 on 6.5", but I'll have to do some looking. If it turns out that there are 8 on 6.5" GMT-900 dually axles then that might be the solution, particularly if they share the same pinion connection to the driveshaft.

 

[TWX]

Okay, this might be going somewhere.

The GMT-900 was a transitional model, they started out 8 on 6.5 in 2007, and remained that way through 2010. 2011 was when the wheel bolt pattern changed.

If the wheel bolt pattern information I found is accurate, 2007-2008 had a 16" wheel and 2009-2010 had a 17" wheel:

The 2011-2014 trucks have a different wheel bolt pattern but the same offset and a 17" by 6.5" wheel, so I expect that the whole GMT-900 platform was vastly similar other than the changes required to go to the different 8x210 (I was incorrect about 8x180, that's SRW only)

I'll have to see what I can find. Trucks should be a lot easier to find parts for than vans.

 

[TWX]

Continuing familiarizing ourself with our new 20 year old Roadtrek 210, on Friday we sought to flush the gray and black tanks and to do a flush and sanitizing of the fresh tanks. This did not go entirely as planned.

We first filled the fresh tanks through their gravity-fill ports and then pumped those through into the back and gray tanks. Right as we began, the momentary rocker switch on the panel broke, stopped rocking. Ended up pulling the switch out of the panel and found that one of the hinge pins had snapped. Disconnected it entirely and we ended up checking the tanks' status by just temporarily bridging the two terminals. Filling the black and gray tanks was otherwise uneventful, and the macerator pump worked to empty them. The water ran clear too, so it looks like the prior owners took care of the tanks,

Where it really went sideways though, we attempted to use the city water hookup. Included with the RV were a bunch of handwritten notes for how the plumbing was reconfigured away from how it left Roadtrek's factory. Unfortunately the instructions and the labels on various valves and fittings did not accurately describe the plumbing. The city connection with the valve for tank-fill didn't stop tank-fill and didn't let water into the system until we manipulated other valves, valves that are not factory. At one point we had somehow made a circuit where the water pump was just sending water around the system in circles.

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We made some progress but hadn't yet flushed the water heater, so we opened that by removing the anode and realized it was getting pretty silted-up inside. Ended up pushing water in via that hole to add pressure, then taking away the hose and letting that pressure forcibl expel the silt. Did this a few times, since there was air in the system and air can compress this would increase pressure without strictly speaking waterhammering the plumbing. Once that we clean we again tried to figure out the plumbing so we could apply P-touch labels, but even after putting the van up on ramps to go underneath I'm still not entirely certain. I will have to go over my notes and try to confirm the various changes that were made.

But both fresh tanks have had their mild bleach solution and since drained, and driving with full fresh water tanks was basically indistinguishable from driving with empty tanks.

Also while under inspecting the plumbing I fixed the shock boots:
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and found a presumably positive wire from the generator I think, in between the axle and the bump stop:
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View media item 447042I temporarily relocated this but need to do a more permanent fix.

In the midst of all this, we opened up the awning and cleaned it a bit. Since it wasn't our primary focus I didn't go nuts, but wanted it clean enough that dust/dirt wasn't going to be falling on us while in the shade.

I'm tempted to relocate the 30A service connector out of the exterior water compartment, as a widebody van there's a gap in the back corner that might allow it to mount out of the way:
View media item 447043We'll see if I do or not. I want to use one of those twisting weatherproofing rings if I do end up doing this.

 

[booster]

210 owners manual. Water system at page G1

https://roadtrek.com/wp-content/uploads/2014/08/2004-Roadtrek_Owners_Manual_2004_Chevrolet_210_models.pdf

 

[TWX]

Ordered the parts to try to put the generator exhaust back together. This is what I've ordered:

P/N	Item	Length	Source	Price
155-2325	Onan Exhaust Tube Kit - 25"	25	https://www.amazon.com/dp/B00I8RZ0OS	$64.65
155-2449	Exhaust Resonator (12" long, 2.5" dia)	12	https://www.amazon.com/dp/B00HSO0BSM	$60.62
	1.25 Inch Exhaust Pipe T304 Stainless, Length 17.3"Straight Tubing, Flared & Slotted End	17.3	https://www.amazon.com/dp/B0G1KH4PFG/132-6494343-3527267	$24.99
	Glarks 2Pcs 304 Stainless Steel U-Clamps 35MM (1-3/8in) Muffler Exhaust Clamps		https://www.amazon.com/dp/B0CWTZX4WS/132-6494343-3527267	$12.99
	PATIKIL 45 Degree Bend Elbow, 1 1/4inch OD Sanitary Exhaust Pipe Elbow	5	https://www.amazon.com/dp/B0DGTVT14L/132-6494343-3527267	$15.09
155-2174	Cummins Onan 1552174 Exhaust Hanger		https://www.amazon.com/dp/B00T36TKH6	$20.59
		59.3		$198.93

I didn't strictly speaking need the little 45° elbow, but I may cut it with a traditional tailpipe-cut at a bevel to make it look nice. I could have gotten the parts from elsewhere a little cheaper, but I would have been saving all of $20 or so and I didn't know when the parts would ship from other suppliers. Annoyingly even the local Cummins dealer doesn't stock the stuff.

Hopefully the 17.3" length of tubing is just what I'm calling for. Haven't decided if the resonator goes right at the very end before the exhaust tip, or further back between the 25" headpipe and the 17" pipe. We'll see when the stuff arrives.

I did buy a second exhaust hanger, I will probably use one right from the generator mounting and a second one from the vehicle frame. That way hopefully I don't drop an exhaust again in the future.

Might need to order or buy an additional exhaust clamp, depends on what fits and if the old one that I took off is still any good or not.

 

[youngnretired]

Interesting. Our 08 210P doesn't have a resonator in the exhaust like yours. I know there's a muffler inside the generator, but nothing except exhaust pipe outside.

Here's a picture of ours. One hanger on the drivers side of the generator and one hanger underneath the water/electrical cabinet.

 

[booster]

The resonator was not on the generators stock, at least until 2007 when ours was built. Very many people added them later to try quiet the thing down some as they are so loud. We added it when we had a generator and it helped some but not a lot. Much better since we took it out for us.

 

[TWX]

I gather that it legally serves as a spark-arrestor, and the National Parks Service requires spark-arrestors for generators now. That's principally why I'm adding it, and why I chose the Cummins/Onan part explicitly. There were some Amazon options that might have done but there wasn't any documentation on how good the actually were.

I received my momentary rocker switch for the control panel, installed it and it's working. Received some of the exhaust parts, the 17.3" tube doesn't quite fit into the resonator. I'll have to evaluate my options once all the parts are in. I might end up having to buy a different piece of tube or perhaps to see if I can work with a swage.

 

[Johnnyfry]

Well, over the last couple of days since buying the Roadtrek 210 we've spend a considerable amount of time cleaning, mending, repairing, etc. We've found no less than four different kinds of tape and two different kinds of bailing wire, and for what amounts to being incredibly simple stuff to have fixed properly.

The biggest issue was the bathroom door. The door was pulling itself apart, the top rail was pulling away from the stile at the hinge-side. Since the top half is mirrors on both sides this seemed particularly problematic, so we took the mirror-panel out and then dismounted the door and took it out to fix.

Of course the prior attempt at a repair had involved duct tape:

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I cleaned it up and used proper wood glue to affix the rail back to the stile and then clamped it:

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After that I took to cleaning up the rest of the door. They apparently had problems with the door rattling in place, and the solution had been to duct-tape random stuff to the door in order to pad it out a bit:

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In the process of pulling all of this off I found what specifically they had used to pad it:

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Cheese. To stop the bathroom door from rattling, they padded it with cheese.


The detector (propane? CO?) mounted near the back bed was held with tape too. This is an electrical component so naturally it was secured with black electrical tape. Peeled all that off, used Goo Gone to clean it up, and then reassembled it properly.


When I got back to the TV I found that it had cardboard washers holding it:

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Obviously nothing EVER will top the cheese, but really, cardboard washers?


We put the bathroom door back on, I'm going to install some magnets and plates to help hold it at the top and bottom, and I might put something on it to press against the door frame when closed to keep it from trying to pull itself apart.

Another thing to be aware of concerning the bathroom door is shifting of the upper door frame. I began having trouble locking the door and it became worse over time. I finally measured the doorframe width at both the bottom and the top of the door and found that the width at the top had decreased, making closing the door problematic. My solution was to cut a 2X2 to match the width of the bottom. I wedged it into the top of the doorframe and it solved the closing problem. Unfortunately, it impinges on the use of the shower curtain so I did not mount it permanently. I am looking for a method of properly securing the door frame to the overhead so I can eliminate the @X@ brace.

 

[booster]

Depending on how thin you need to go to clear the curtain, the easiest would probably be to push it out with the spacer and use a piece of aluminum bar across with angle cleats to the bar and side walls and then remove the 2X2.

I think you have a 2006 and they show both the aisle and full time bathrooms for that year in 210s. I should have asked which you have.