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GaryS1953
Michigan
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To Grit dog, By the way, forgot to mention that the previous owner had flipped the axle on this trailer. Not sure why. Seems to me with adjustable hitches it really only makes sense to do it on 5th wheels, not TTs. In any case, could that be contributing to our issues?
Gary in Michigan
2014 Chevy Silverado 1500 Double Cab 5.3 Liter V8
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JRscooby
Indepmo
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GaryS1953 wrote:To Grit dog, By the way, forgot to mention that the previous owner had flipped the axle on this trailer. Not sure why. Seems to me with adjustable hitches it really only makes sense to do it on 5th wheels, not TTs. In any case, could that be contributing to our issues?
That can really make a difference in the way a trailer handles. If done right, raising COG is never a good thing. Add the fact it would be hard to be sure it was done right.
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opnspaces
San Diego Ca
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Hi Gary, when you say your tires have a max load of 35 PSI where are you getting that number? Is that on the sticker on the drivers door jamb or on the tire itself? The tires should have a max pressure of 45PSI cold embossed directly on the sidewall of the tire.
I would at least put the rear truck tires at max cold (max cold is first thing in the morning before you drive more than a few blocks) But as Grit says if the 45 is still not right you can try 65 PSI and drive it for a few miles for a test.
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valhalla360
No paticular place.
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What is the weight rating on the side of the tire? If 35psi is the max pressure, the tires may have a lower rating than the rear axle. Soft squishy car tires may be fine running around empty but overload them and the ride can get squirrely and you risk a blowout.
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wnjj
Cornelius, Oregon
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GaryS1953 wrote:To Grit dog, By the way, forgot to mention that the previous owner had flipped the axle on this trailer. Not sure why. Seems to me with adjustable hitches it really only makes sense to do it on 5th wheels, not TTs. In any case, could that be contributing to our issues?
Flipping TT axles helps with ground clearance. The previous owner may have had a parking space with a steep angled driveway to back into.
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GaryS1953
Michigan
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opnspaces wrote:Hi Gary, when you say your tires have a max load of 35 PSI where are you getting that number? Is that on the sticker on the drivers door jamb or on the tire itself? The tires should have a max pressure of 45PSI cold embossed directly on the sidewall of the tire.
I would at least put the rear truck tires at max cold (max cold is first thing in the morning before you drive more than a few blocks) But as Grit says if the 45 is still not right you can try 65 PSI and drive it for a few miles for a test. Oh boy, now I'm feeling REALLY stupid. I could swear I saw it on the tire, 35 max PSI, but you are right, it says 44 PSI. I will be airing them up shortly.
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Grit dog
Black Diamond, WA
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44 will help. Try 55 to see how stout tires feel. You still have marginal at best tires.
Flipped axles shouldn’t matter at all except a little higher center of gravity. Won’t make it buck more.
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GaryS1953
Michigan
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Ok for those still following this thread and offering advice - I went back to the Cat scale, hope I've got this right.
1st ticket -Steer Axle only 5,780 The truck on only one pad.
2nd ticket Steer Axle 3,260
Drive Axle 3,460
Trailer Axle 5,940
Combination 12,660
So I added the two truck axle weights, then subtracted the truck weight, and I get a difference of 940, divide by the truck actual weight of 5780, and I get 16.26% Am I doing that right?
Also, I overinflated the truck tires to 55 psi, and it seemed to help with small bumps, but large bumps still cause what I call bucking, where the front and back of the truck jump up and down, and I still feel like the truck is too light in front and it seems difficult to keep the truck going straight down the road. Next thing I guess I'll probably try is adding leaf spring helpers as Grit dog suggested. Any particular type recommended? Not exactly sure what I'm looking for.
Finally I borrowed a 3/4 ton Chevy Duramax and towed the camper with that. Still, some very minor bucking, but it was like night and day, and, perhaps even more importantly, I could steer with one hand, it was that stable in the front.
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valhalla360
No paticular place.
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GaryS1953 wrote:Ok for those still following this thread and offering advice - I went back to the Cat scale, hope I've got this right.
1st ticket -Steer Axle only 5,780 The truck on only one pad.
2nd ticket Steer Axle 3,260
Drive Axle 3,460
Trailer Axle 5,940
Combination 12,660
So I added the two truck axle weights, then subtracted the truck weight, and I get a difference of 940, divide by the truck actual weight of 5780, and I get 16.26% Am I doing that right?
Also, I overinflated the truck tires to 55 psi, and it seemed to help with small bumps, but large bumps still cause what I call bucking, where the front and back of the truck jump up and down, and I still feel like the truck is too light in front and it seems difficult to keep the truck going straight down the road. Next thing I guess I'll probably try is adding leaf spring helpers as Grit dog suggested. Any particular type recommended? Not exactly sure what I'm looking for.
Finally I borrowed a 3/4 ton Chevy Duramax and towed the camper with that. Still, some very minor bucking, but it was like night and day, and, perhaps even more importantly, I could steer with one hand, it was that stable in the front.
Technically wrong but decipherable. 1st Ticket should have had the truck axles on separate pads but close enough we can figure things out:
- Truck goes from 5,780 to 6,720 (3260+3460), so the hitch weight is 940lb as you calculated.
- Trailer weight is 5,940 + 940 = 7,880lb. (within the trailers 9,462GVWR)
- Hitch percentage is 940lb/7,880lb = 12% (OK range)
I'm betting the 35psi is causing a lot of the issue. What was the weight rating off the side of the truck tires? At 45psi, it might be OK.
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wnjj
Cornelius, Oregon
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GaryS1953 wrote:Ok for those still following this thread and offering advice - I went back to the Cat scale, hope I've got this right.
1st ticket -Steer Axle only 5,780 The truck on only one pad.
2nd ticket Steer Axle 3,260
Drive Axle 3,460
Trailer Axle 5,940
Combination 12,660
So I added the two truck axle weights, then subtracted the truck weight, and I get a difference of 940, divide by the truck actual weight of 5780, and I get 16.26% Am I doing that right?
If you are trying to calculate the percentage of tongue weight, you should divide by the trailer's total weight. So 940/(12660-5780) is about 13.7%. Still good though.
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