Truck bed camper shim

[Supercharged111]

My Lance has always say ass down in the bed. I'm wondering what you guys have done for shims? I had an old piece of plywood lying around and cut about a 42x48" piece and put it in the back half of my bed. I used my planer to taper the leading edge. I'm wondering if I should have cut it shorter? The camper is about dead nuts level now.

[Longshore]

Thanks Geo*Boy and Moresno. I will do that.

[MORSNOW]

Geo*Boy wrote:

Longshore wrote:
I have the short bed I guess I can find mud flaps and slide them under the mat front and back. I did notice a pretty good rock backwards when stopping, but the truck was real low on the back and I thought that was the cause.

If the gap is in the back, just place the flaps in the back to compensate for the crown.

That's what I did. Just placed the rubber mud flaps under the rear portion and under the full bed rubber mat.

[Geo_Boy]

Longshore wrote:
I have the short bed I guess I can find mud flaps and slide them under the mat front and back. I did notice a pretty good rock backwards when stopping, but the truck was real low on the back and I thought that was the cause.

If the gap is in the back, just place the flaps in the back to compensate for the crown.

[Longshore]

I have the short bed I guess I can find mud flaps and slide them under the mat front and back. I did notice a pretty good rock backwards when stopping, but the truck was real low on the back and I thought that was the cause.

[Geo_Boy]

Longshore wrote:
I checked my 2015 GMC 3500 and yup a four foot level rocks about 1/8" centered over the drive axle. You can't really see it till you get down and look straight up the floor of the bed. But with a one inch stall mat would this be an issue?

There is a 1/2” difference on a long bed. I placed a 20” wide X 1/2” thick piece of rubber mat across the back of my 2015 GMC 3500 bed, on top of my bed mat, and it took the rocking motion out of my TC.

[Longshore]

I checked my 2015 GMC 3500 and yup a four foot level rocks about 1/8" centered over the drive axle. You can't really see it till you get down and look straight up the floor of the bed. But with a one inch stall mat would this be an issue?

[notsobigjoe]

Slymer wrote:
Ours always looked tilted too & it made no sense. Finally figured out something. Take a 5 ft board & put it across both bedrails, just behind the back window. Now take a measurement from the bottom of that board to the truck bed. Now take that board and move it back just forward of the tailgate & take that measurement again. On our 2011 F350 there was almost an inch difference if I remember rightly. Basically a manufactured optical illusion. No idea why, so I just got used to it.

Mine too, I'm gonna try that this weekend. Thanks

[Avid_Fox]

My Ford SD 350 bedrails are higher at the back than the front, so it does look tail heavy with TC on. Bed is also crowned some, about .5" or so just in front of rear axle. Rubber shims at the tail made it feel less rocking horse like.

It's annoying, but not troublesome.

[Grit_dog]

Supercharged111 wrote:
I don't think the 97 bed is crowned, I'd have to take a straight edge to it to be sure as was mentioned. I also used my planer to taper the edge. If I'm only using the 1 piece, I'm thinking the shorter one will be better. I thought more people had done the shimming, I do like the stepped semi mudflap idea though. I'll have to check again, but I don't think the rails are tapered either.

If you're going through all this trouble, why not just measure the depth of the truck bed and the depth of the camper and see which one is not parallel front to back?

Presume it's the truck. Same thing on our old Dodge and doesn't affect anything, functionally.
But if the aesthetics bothers you, then I suppose your planed super duper wedge is the best option as it provides a good deal of support?
That said, IMO this is a solution looking for a problem.

[mkirsch]

If the crown was the problem, you'd notice the camper rocking fore and aft over the crown.

There's no magic. Your camper is sagging in the rear, or is flexing the truck bed.

With your truck being 24 years old and the camper being 14 years old, it is possible the something is getting fatigued.

[Supercharged111]

I don't think the 97 bed is crowned, I'd have to take a straight edge to it to be sure as was mentioned. I also used my planer to taper the edge. If I'm only using the 1 piece, I'm thinking the shorter one will be better. I thought more people had done the shimming, I do like the stepped semi mudflap idea though. I'll have to check again, but I don't think the rails are tapered either.

[kohldad]

You are asking for problems supporting with a piece of plywood that doesn't give. As mentioned, it is the truck bed rails that taper. If the look really bothers you, then I would make a platform that supports the entire bottom of the camper that is tapered the entire length to match the bed rail taper.

I'm not OCD about so have no problem with the difference in gap between the camper and truck bed rail. I'm engineer so once I saw the gap and new what was causing the difference, it no longers bothers me.

[Ski_Pro_3]

My 2006 Dodge RAM diesel short bed is the same way; shallow at the cab, deeper at the tail gate. It really bothered me, the way it looked so I did something about it.
I used a full length rubber bed mat made for my short bed truck and cut the front 1/3 off and laid that over the end close to the tail gate. This made the bed a 3-step level with 2 layers of rubber mat at the tail gate, 1 layer in the middle and zero layers near the cab. This made it so the camper was now even with the side rail of the bed. Measuring between the camper and the top of the bed is now within 1/4" front to back. The rubber flexes and gives so the load is pretty much even across the bottom of the camper.

[MORSNOW]

GM truck boxes are not flat, they have a peak across the bed by the wheel wells to allow water to drain from the front and rear of the box. Campers will rock on this peak unless a shim is placed in the rear. I used two semi truck mud flaps under my rubber mat to make a level surface. Use a straight edge, like a 4' level and slide it on the floor of the box from front/rear and you will see the peak.