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Hey everyone.

I want to use the same 17" stock steel rims and Michelin tires I'm running now, on both the truck and 7x16 trailer I'm having custom built. Space will be scarce on this mini toyhauler being built by Jensen Trailers, so I don't want more than one or two spares. I would consider 17" aftermarket rims with the stock offset all around though.

This is the goal, but I haven't come up with any info on how much larger the center hole of the trailer rim is compared to the truck rim, or if its a unsafe idea. Or how much offset stock dodge rims have compared to the centered trailer rims. Anyone?

How would I go about enlarging the center hole on stock steel rims to fit over 7k trailer hubs? Or would there be a different approach to my goals I'm not aware of? A aftermarket rim?

Thanks!

texasprd

I would think the trailer manufacturer could tell you hub and bolt-circle diameter. Obviously, you'll also need to determine those dimensions on the OEM steelies if you haven't already, and compare against the trailer hub dimensions.

If the trailer is 16' length, are you running dual axles for a gross trailer weight of 14k? Does the max combined weight capacity of the LT tires you want to run equal/exceed the (combined) axle capacity?

A machine shop might be able to enlarge the center hole if needed - but bear in mind that the center hole is flanged (at least on every steel wheel I've noticed) and probably serves to strengthen the wheel. For safety, I would recommend an aftermarket wheel over enlarging the OE center hole.

rebar

Thanks texasprd.. Ive found out the hard way if I ask to many questions or requests, salesman ignore me. I feel lucky Jensen trailer will let me supply wheels etc etc, but maybe I need to go there and measure before they ignore my requests to. lol Like walking on egg shells, because few are willing to build the narrow track I want. Maybe I can contact the axle manufacture, as they must have pilot hole size's available..

My target weight is around 8k wet and the axles are over kill to ensure I don't bend one off road or on the yukon highway. But I will have to modify the spring rate or de-leaf. I'm doubting or questioning if run of the mill 2' trailer leaf springs will be adequate though.

Good point about the flange..

SIXSLUG

Most salesman don't know is why they don't answer. Better than getting bad info I guess. I like the points Texasprd made regarding modifying a steel wheel. IIRC our heavy trailers are teh old standard 8 lug spread, which is what DOdge still used at leaset thru 2002....Ford and Chevy are different.

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notoriousGood point sixslug..

After some research, Ive found the hub diameter of most 7k trailer axles is 4.75 which match's the dodge rim. But the offset of the truck rim will prematurely wear out the trailer bearings, so a better plan is to use a trailer rim and tire as the spare for both truck and trailer.
I will use LT235/85R16 Michelin Defender LTX M/S tires on 16x7 rims on the trailer, because the outside diameter is only one tenth of an inch different than the LT265/70R17 Michelin's I'm running now.

The only issue about my plan is Ive been told or heard trailer rims aren't held to the same standards truck rims are.. And I better have the tire tech check the run-out of the rims before buying and that the center pilot hole's are notorious for being off center.. The dodge rim is mounted both lug centric and hub centric, so I'm a little concerned in the event of a flat that running a trailer rim on the truck might not be the best idea since it would be mounted lug centric only.
The center hole in a automotive wheel on our trucks is closely matched to the wheels center unlike a center hole in a trailer wheel is just for clearance and not closely matched.

SIXSLUG

Hmmm, good info...if you flip them around will the bearings last twice as long?? Just kidding.

We run 8 lug wheels on our equipment trailers but with dedicated trailer tires. I didn't know about the offset regarding bearing wear.

Good info!

u2slow

Trailer stuff is built around 14-16", or 17.5" wheels, about 6" wide, with close to zero offset. (i.e. the flange is in the middle of the wheel.) '00+ Dodge wheels have ~2" extra backspacing and are 7.5-8" wide.

IMO, your best bet for using a truck spare on the trailer is a ~2" spacer. Knocks your wheel down to a more 'normal' 4" backspacing; placing the load over the center of the bearings again. There's still the matter of keeping the tire off the springs, and under the fender. In-boarding the spring de-rates the axle rating (leverage).

Thinking outside the box a little.... perhaps you can harvest some SRW spindle/hub ends off some junk Dodge diff housings and connect them with a straight tube. The bearings are much larger than on a trailer axle and will put up with Dodge-offset wheels just like stock.

rebar

Thanks u2slow.

If I had a junk yard like you I might try that, but for now I'm going to use the centered trailer rims on the trailer. And also plan on using the trailer spare for the truck as well. But as mentioned, I need to find well made trailer rims.

u2slow

I've built more than one trailer out of recycled truck parts.

Technically, most trailer tires and wheels are marked 'for trailer use only'. The problem may be the uneven loading of a zero-offset wheel on modern unit-bearing vehicle. I do know a trailer tire and wheel have to put up with the extra side loads and scrubbing you get from turning hard with tandem/tridem setups, so they are likely stronger, Also not sure how many folks check and obey the weight rating of the aftermarket wheels shops happily sell and install. I see 16" trailer wheels rated up to 4080# on this page: 16 inch Trailer Rims Wheels, Aluminum, Chrome, Steel, Painted, Galvanized, Custom Trailer Wheels

IMO, a wheel with tapered lug seats does not require hub piloting. I have two factory D250s (1/2" stud Dana 70s; 5450# rear GAWR) where the hub is undersized for the OE wheel. Bigger studs will no doubt carry more.

Another thought... it may be possible to have 17.5" alum wheels machined down a half inch. This is done to 22.5" semi-truck wheels to fit lighter/sportier tires.

rebar

I'm pretty sure some folks are running allot less offset or centered rims on their dodge trucks, so I'm less worried because I haven't heard of any related failures.. I have read first hand about trailer bearing failing because of truck rims placing the load on the wrong place though..

I "think" my studs are 9/16", but I'm a bit concerned because have been told dodge rims use both hub-centric and lug-centric mounting methods.. I'm hoping if I buy decent american made trailer rims, all the holes provide support.

This trailer rim looks strong. But its 16x6 instead of 16x7. The only 16x7's are fancy aluminum and I want to look poor when I'm in south america.

u2slow

The wheels can be centered one way or the other. Not both ways. The hub is a few thousandths smaller, maybe even a ~1/4" smaller, to let the tapered seats do the job. 16x6" or 16x6.5" wheels are quite ideal for 235/85R16. For a 7" wide wheel, 245-285 sizes fit better. M14 or 9/16" studs are pretty much the norm for 8-lug... 93-older Dodge is one of the exceptions (1/2" SRW or 5/8" for DRW).

Trailer bearings are similar to the front of a 2wd truck (before they went to unit bearings)... rated to carry more weight than on a truck. To a point where loading the bearing set on-center is critical; especially with the side-loading you get manoeuvring tandems/tridems. I move a lot of trailers for work... its scary watching what little 5-bolt tires, wheels, and axles do on a car-hauler when turning hard because the owner has a diesel crewcab on the deck.

Supposing you spec a pair of 7-8k# axles on a 10k# gross trailer, you'd have more leeway on wheel offsets and how far the wms is from the leaf spring. The pounding of unpaved roads (or no roads) is another reason to up the axle rating. Larger bearings can take more abuse at a given weight. The tricky part is calculating how much 'less-than-ideal' setups and circumstances de-rate the axle.

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That's been my plan for the 7x16 toyhauler I want for a while.. Mix and match 7k straight axles on 4000# springs, because one axle will drop into a low spot and shift the load to the other on the crap roads I want to travel. Bump stops to

What would you use for equalizers? And would you buy double eye or slipper springs?

u2slow

I'm not sure of the pros/cons of each.

What does look intriguing is rocker-beam or walking-beam setups... but seems to be limited off-the-shelf solutions. Good reading on building trailers here...
https://mechanicalelements.com/video...torsion-axles/

rebar

Yes I agree if it looked like this..


https://servi

The only one I thought was worthy was the timbrin Tandam Silent Ride , but when it twists when left front and right rear drops in a rut at the same time, the control arms and bushings are going to take hella twisting motion. I don't like it.

rebar

I'm second guessing my 16" trailer rim choice now because don't most new trucks come with 17" rims now? Which might mean 16" tires may not be as easily found out on the road, or less choices? I ran Bridgestone Duravis R250's on my old toyhauler. But Im reading good things about Goodyear G614 and Sailun S-637's

What's your take on the ST vs LT tires on a trailer debate? The sailun's say it can be used for both..