laknox
Arizona
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We all talk about bed clearance for our hitch heights, and clearance =between= tires, but what's a good rule of thumb (if there is one) for clearance on =top= of the tires, to the wheel well? I've thought about upgrading to 16" rims, but would lose nearly 1" of clearance between my tires and the wheel well if I stay with a similar tire diameter (tire-to-tire clearance is OK). I =don't= want to go smaller as I already tow a touch nose-high and, as my last boondocking trip showed, I =need= that 8+" of bed rail clearance. Anybody regularly hit their wheel well in what you'd consider "normal" use (i.e. going over speed bumps in a park or gutters crossing sidewalks, etc.)?
Lyle
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JIMNLIN
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16" tires is a lot of tire capacity for a 25' 5th wheel.
Lots of different reasons a same size tire may work without clearnce issuse on one trailer but won't work on another.
My std leaf spring suspension on my RV trailer tires rubs lightly at the top of the wheel well on some deep drain gutters on some streets. It hasn't been a issues in over 80k miles and on the second set of tires.
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laknox
Arizona
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JIMNLIN wrote:16" tires is a lot of tire capacity for a 25' 5th wheel.
Lots of different reasons a same size tire may work without clearnce issuse on one trailer but won't work on another.
My std leaf spring suspension on my RV trailer tires rubs lightly at the top of the wheel well on some deep drain gutters on some streets. It hasn't been a issues in over 80k miles and on the second set of tires.
Even though my rig is a model "25FSG", it's 29'3" OAL, with 11,300 GVW. I went with E-range tires for extra capacity. IIRC, I have ~4" at level, between the top of the tires and the wheel well.
Lyle
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SoCalDesertRider
SanDiego, CA, USA
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If you have independent torsion axles, the tires will drop or stuff less when diagonally crossing a rut in the road or going over a speed bump, since what the one side of the axle does, doesn't affect what other side does nearly as much as a leaf sprung suspension. Torsion axles can also be adjusted for ride height by rotating the position of the spindle arm on the spring end to the next notch, or by rotating the spring inner position end within the axle.
Leaf sprung monobeam axles travel more equally up/down in opposite directions when one side goes into a rut and the other is on flat ground, or when one side goes over a speed bump and the other is on flat ground. Also, your spring stiffness will affect how much the suspension can compress. You could upgrade to stiffer, taller springs if you need more vertical clearance for larger diameter tires.
To raise your trailer, you may also want to consider either doing a spring over axle conversion, or lowering your leaf spring and shackle mounts on the spring hangers, if they are adjustable, or building a square tube sub frame under the trailer's frame to hang the spring hangers from.
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laknox
Arizona
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SoCalDesertRider wrote:If you have independent torsion axles, the tires will drop or stuff less when diagonally crossing a rut in the road or going over a speed bump, since what the one side of the axle does, doesn't affect what other side does nearly as much as a leaf sprung suspension. Torsion axles can also be adjusted for ride height by rotating the position of the spindle arm on the spring end to the next notch, or by rotating the spring inner position end within the axle.
Leaf sprung monobeam axles travel more equally up/down in opposite directions when one side goes into a rut and the other is on flat ground, or when one side goes over a speed bump and the other is on flat ground. Also, your spring stiffness will affect how much the suspension can compress. You could upgrade to stiffer, taller springs if you need more vertical clearance for larger diameter tires.
To raise your trailer, you may also want to consider either doing a spring over axle conversion, or lowering your leaf spring and shackle mounts on the spring hangers, if they are adjustable, or building a square tube sub frame under the trailer's frame to hang the spring hangers from.
With a near-7 year old trailer, and no other issues, I'm just not willing to dump a ton of cash into it and I really don't need a 4" lift, especially just to get 1-2" clearance for taller tires. I just got off the phone with a local spring shop, and they get ~$750 for an axle flip, wet bolts and EZ-Flex equalizer. WAY more than I want to spend, especially when I can do some of the work myself.
Lyle
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SoCalDesertRider
SanDiego, CA, USA
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If you can do the work yourself, you should be able to do a spring over axle conversion for less than $100 in parts (4 spring perches, 8 u-bolts and nuts), if you don't have shocks on the trailer. If you have shocks, add the cost of 4 new, longer shocks.
If you can do the work yourself, you should be able to do a sub frame lift for about the same cost as an axle flip, just the cost of the square tube to make the sub frame with, if you re-use the spring hangers. If not, new spring hangers are not expensive.
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Cox89XJ
Tennessee
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A LT225/75R/16E is only one inch taller than a ST225/75R/15D. With the tire one inch taller, it will only be one half inch closer to your fender well. This is what I did and it fit on a 04 Keystone Laredo. When I traded it, I put the tires on a 06 Cougar and the 16 inch tire and wheels fit them both. Most will fit. You can google tire size chart.
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45Ricochet
North Idaho
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" $750 for an axle flip, wet bolts and EZ-Flex equalizer"
That's a good price IMO. Heck IIRC my wet bolt kit was almost a $100 from Mor/ryde.
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laknox
Arizona
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At this stage, given the age of the trailer and our current low usage, I'm just going to live with what I've got. Might spend the $ on a wet bolt kit and equalizer, and do it myself...might not. Thanks to all who have responded.
Lyle
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smkettner
Southern California
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My smaller trailer has about 2.5" OEM clearance and there is evidence that is may rub a bit with the right conditions. I would not go less than 3" and that is pushing it. 2" taller tire will reduce fender clearance by 1". Consider some slightly longer shackles.
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