Frame Stiffing to reduce Porpoising?
Got a question for you seasoned drivers with older rigs. I have a 1999 F350 Dually Quad Cab Long Bed. I've been driving it for thousands of miles and for the most part, it's been fine. However, while ...
Forum Discussion
Thanks all for the thoughts. So a few thoughts from people's comments.
1. The camper isn't all the way forward because it had rubber stops that are about 2.5" long that are mounted on the bottom front of the camper that go up against the front of the bed of the truck. I removed those but kept the spacing the same as I have a 2"x12" board that sits across the front of the bed and is notched to hug the camper and keeps it moving side to side. If I redid this with metal, I should be able to reclaim about a 1.5" to possibly 2" for the camper to move forward.
2. Those that think their truck doesn't porpoising probably just don't notice it. Some trucks will obviously handle this better than others. The easiest way to tell though is if you look up at the overhead portion of the camper right above your head while driving and see it moving up and down, that movement is because your frame is flexing as you drive. I get between 1" to maybe 2" of movement on rough roads. What I am also looking at is in the side view mirror, looking along the bed rail at the back where the tail lights are. You will see similar movement as the frame flexes. Now, short bed trucks or regular cab trucks obviously will have less flex. My truck being a crew cab, long bed with just a C channel frame obviously shows quite a bit of movement.
3. Buying a new truck is not in the cards. To get the same style of truck I'm looking at $70,000+, maybe closer to $90,000 by the time taxes are added in.We use the truck just a couple of times a year, otherwise it sits in indoor storage with the camper. Hard to justify a car payment nearing $1500 a month for a vehicle that gets less than 5000 miles a year. Now, if money where no problem, heck yeah I'd be down at the dealership buying a new truck but that ain't my life. That being said, I don't think I would end up with a new truck if we were out shopping. With two late teenagers and two toddlers, our future if I can persuade the Mrs. will likely have something like this in it.
4. I did just replace my shocks (Bilstiens previously that where rather worn out) with KYB Monomax shocks and I think that helped quite a bit. Would have liked to have some adjust-ability like the Rancheros have but they were not available at the location and time frame that I had to work with.
5. Getting back to the expense of strengthening the frame. Even if I spend $3000 to $5000 to have it done, I'm still way ahead of buying a new truck. The other thing is, my truck is only two wheel drive. Fine for California but my plan will be to start going to areas where there may be snow and ice and I don't want to be doing that in a 2 wheel drive truck. So the longterm plan is to take the truck to a 4x4 shop and have them do a 4x4 conversion on it and while they do that, they can add rigidity to the frame. Yeah, I know, it's extreme measures but even if I put $10k to $20k into this route, I'm still WAY ahead of a $70k to $90k new truck (and used trucks aren't all that much cheaper these days).
1. The camper isn't all the way forward because it had rubber stops that are about 2.5" long that are mounted on the bottom front of the camper that go up against the front of the bed of the truck. I removed those but kept the spacing the same as I have a 2"x12" board that sits across the front of the bed and is notched to hug the camper and keeps it moving side to side. If I redid this with metal, I should be able to reclaim about a 1.5" to possibly 2" for the camper to move forward.
2. Those that think their truck doesn't porpoising probably just don't notice it. Some trucks will obviously handle this better than others. The easiest way to tell though is if you look up at the overhead portion of the camper right above your head while driving and see it moving up and down, that movement is because your frame is flexing as you drive. I get between 1" to maybe 2" of movement on rough roads. What I am also looking at is in the side view mirror, looking along the bed rail at the back where the tail lights are. You will see similar movement as the frame flexes. Now, short bed trucks or regular cab trucks obviously will have less flex. My truck being a crew cab, long bed with just a C channel frame obviously shows quite a bit of movement.
3. Buying a new truck is not in the cards. To get the same style of truck I'm looking at $70,000+, maybe closer to $90,000 by the time taxes are added in.We use the truck just a couple of times a year, otherwise it sits in indoor storage with the camper. Hard to justify a car payment nearing $1500 a month for a vehicle that gets less than 5000 miles a year. Now, if money where no problem, heck yeah I'd be down at the dealership buying a new truck but that ain't my life. That being said, I don't think I would end up with a new truck if we were out shopping. With two late teenagers and two toddlers, our future if I can persuade the Mrs. will likely have something like this in it.
4. I did just replace my shocks (Bilstiens previously that where rather worn out) with KYB Monomax shocks and I think that helped quite a bit. Would have liked to have some adjust-ability like the Rancheros have but they were not available at the location and time frame that I had to work with.
5. Getting back to the expense of strengthening the frame. Even if I spend $3000 to $5000 to have it done, I'm still way ahead of buying a new truck. The other thing is, my truck is only two wheel drive. Fine for California but my plan will be to start going to areas where there may be snow and ice and I don't want to be doing that in a 2 wheel drive truck. So the longterm plan is to take the truck to a 4x4 shop and have them do a 4x4 conversion on it and while they do that, they can add rigidity to the frame. Yeah, I know, it's extreme measures but even if I put $10k to $20k into this route, I'm still WAY ahead of a $70k to $90k new truck (and used trucks aren't all that much cheaper these days).
