Unstable trailer - what changed?

[The Warden]

Hello!

I moved a trailer today from Napa to Redwood City. This is actually an annual thing for me; the local Sea Scouts hold a competition in Redwood City every May, and this trailer's basically a chuckwagon. It belongs to some obscure group in Napa; if you take a look at the picture below, you may get a clue as to what the group is.

However, moving this trailer this year was different than in previous years.

I'll start out by saying that this trailer is ancient, and as a result isn't exactly safe to begin with. It's got a 2 5/16" hitch, but it's a single axle with no trailer brakes and no WD/antisway setup. Up to this year, my truck's been the only SRW truck that can safely pull it at 50mph. I know that this trailer desperately needs at least a set of trailer brakes and a WD/sway control setup, but it isn't my trailer and I don't get to make decisions that involve modifying it.

Now, for today. First, it was raining off and on, so the roads were fairly slick. I hooked up to the trailer and started moving. I made a left turn out of Napa onto a small highway, and looked in the mirrors to see the trailer fishtailing I hadn't taken the turn too quickly, either. I attest that to slick roads, unless someone has another thought.

However, another issue arose. For reasons I'm trying to determine, the trailer was a LOT more unstable this year than it has been in previous years. Instead of being able to safely maintain 50mph, I had to keep the speed down to 35mph to keep the trailer from swaying all over the place. This made for a long and unpleasant trip (a 1 hour trip that wound up taking 2 1/2 hours)...and I'm almost scared to try it again.

Now, for the question...does anyone have any idea what might have made the trailer more unstable? I DID replace the tires in the last year...and the new tires are 255/85R16 tires with a "D" load rating, capable of handling 3000lbs each. The weight rating's comparable to the stock tires that these tires replaced. Other than the tire replacement (and engine stuff, but that shouldn't have changed anything), the truck's stock. The trailer tires looked okay.

So, do I need to go back to stock tires to handle this trailer semi-safely, or was the weather the deciding factor, or what?

Thank you!

 

[Whit]

I would say that maybe you need more air in the tires and another thing that may have changed its handeling is the amount of tongue weight, I cant remember how much % tounge weight is needed but is the difference in maybe a loaded vs. unloaded water storage tank in the trailer........something like that can change them drastically

 

[towcat]

tim-
you've seen the tires I run for towtrucks. i like to get the stiffest sidewalls and casings money can reasonably buy. Just as a wise-ass guess, you have a little too much sidewall movement on the tires you have right now. I don't want to be you bringing that trailer back to napa. I can just see the nightmare unfolding when you are coming off the GG bridge going down that grade.

 

[FaC]

I would look at the tongue weight first - IIRC it should be 10-15% of the total trailer weight. I would also look at the hitch height. I would want it level at worst. On my TT I run about an inch down even with a pretty good WD setup. As far as the tires go, I would go to range E tires to get the stiffer sidewalls.

FWIW - FaC

 

[Helipilot500E]

I'd say tongue weight also, and point you to look to see if there is a bunch of stuff that was moved inside behind the axle. I once made the mistake of towing a trailer that was loaded abit too heavy aft of the axle, and was passenger on another trip with a friend towing a trailer loaded the same (aft heavy) they both acted the same way you are decribing

 

[The Warden]

Whitmore, there aren't any storage tanks in the trailer; it's meant to function on city water and power. Regarding tongue weight, the trailer hasn't been altered in any major way...all the appliances that were in it before are still there, and nothing was added. The hitch would be 1 inch taller than it was before because of the tires, but would that make a significant difference? The tires were at full air presssure, BTW.

Calvin, I'm thinking the same thing with the tires...it actually crossed my mind even as I was driving down, if nothing else, because this seems to have been the only major change. I'm going to talk to Big-O in the next couple of days; these tires only have a few thousand miles on them, and maybe something can be worked out. I just wish I had known more about this when I got the tires in the first place...someone on TDS told me that the D-range would be fine, and no one contradicted him, so I assumed "the group" was in agreement. Lesson learned, I suppose BTW, I'm not dumb enough to try going through San Francisco with this monster we came down the 80/880. That said, the area around Pinole just south of the Carquinez Bridge wasn't exactly a walk in the park either...

FaC, the trailer was pretty level when hooked up to the truck. Again, the trailer wasn't really modified, so unless 1" of height makes that much of a difference, I don't think that was the problem...

HeliPilot, the trailer only has a few small things (paper plates, plastic forks, napkins, etc) in it besides the major applicances (which are all permanently installed). The loose stuff was in the back, but I don't think it all weighs enough to make a difference...

Thank you all! I was thinking it was the tires; good to hear that I'm not alone in that train of thought...

 

[towcat]

tim-
save your breath on trying to get something out of "bigO" on your tires. You don't tow that frequently and IIRC you were looking at trying to get the largest tire you can find on a stock ford rim. there's some personal responsibility there. While you can get a better off-road bite with your setup, towing is going to be a problem with those sidewalls. Best thing to do is get another set of rims and mount a pair of towing type tires on it and swap out when you need to tow. You aren't going to get the best of both worlds unless you are willing to do some work.

 

[The Warden]

Calvin, I hear you...I wasn't talking about going in and demanding that the shop do a straight exchange due to a mistake I made. Sorry if it sounded like that in my last post. Just, I seem to remember them saying something about buying tires back on a pro-rated basis based on mileage and wear. I could have that completely off, but I figure it's worth at least going in and asking.

I was actually trying not to compromise on weight-handling when I got these tires (in fact, the question I was initially asking in the original thread on TDS was which of the two E-range tire sizes I should go with). But, in the thread I was asking about tire weights in (here's the original thread on TDS), people were telling me that the physical weight capacity of the tires was more important to consider than the "Load Rating" letters. From what you've said and what I experienced yesterday, it looks like that was off-base...and, had I known that at the time, I would have stuck with the E-rated tires without thinking twice. The extra height was more of a bonus than anything else, and with the ZF5, isn't as critical at this stage in the game. I may not be constantly loaded, but I do tow more than I off-road. Some people did mention the ply difference between the load ranges in the original thread, and I should have paid more attention to that than I did. Failing to do that was my big mistake here, and I take full responsibility for it.

You're right that I'm not going to get the best of both worlds short of having two sets of tires, but $$ won't permit that. Besides, I think it's about time for me to come to terms with the fact that, as much as I like playing in the desert, this truck spends most of the time on paved highways, and the time I do spend off-road (and the sort of off-roading I do) doesn't even come close to needing anything larger than stock. In addition, even with an empty truck, there are handling issues that have come up (mainly the wandering I've mentioned a few times on the IDI board) which may well be attributed to the tires.

I figure at this point that I'll see if that pro-rate thing is a figment of my imagination or if there's some truth to it. If it's true, I'll go back to the stock height, and may also switch to "conventional" all-terrains. If it's a figment of my imagination, I'll keep this thread in the front of my mind for the next time I change out tires, and be damn careful with the truck in the meantime...or see if someone with stock-size tires wants to trade.

Thank you again...

 

[argve]

btw your link only leads me to google... must be something with linking to tds from this site...

I learned this same lesson here just a few weeks ago when I got new tires for the Goat. I went and purchased E rated tires for the rear and learned that not all E rated tires are created equal... I went the cheap route and got tires.com branded tires from Discount Tire here locally - I couldn't force myself to cough up the $150+ per tire for the goodyear commercials that were on there and boy oh boy do I get side wall lean when the trailer is hooked to the back. Yes I do get a little push from the trailer even with the Goodyear Coms on there but nothing like this POS Pathfinders... I guess they got the name right because they find their own dang path - just too bad it's not the path as I want to take... I'll be swapping them out before we take another long trip with the TT. Short trips are ok but lugging for all day with the back end sort of "falling over" as it feels is not on my want to do again list...

I guess you get what you pay for type of thing... (said while having egg on my face).

 

[The Warden]

Travis, that's weird...it stil works okay from my computer. Like you said, TDS is probably being weird... *sigh*

Thanks for the heads-up! You would think that they would need to build each tire to the same standards...that's actually pretty scary that they don't. So, the big question now is, how the sam-hill can you tell the difference? I've got Big-O X/T's on the truck right now; I'm thinking about the Big-O A/T if I can get a new set soon...but if not all tires are created equal, is there a way to determine if this tire's any good without finding out "the hard way"? While Big-O's brand tires aren't exactly cheap in terms of price (IIRC, the X/T's were about $170 apiece), and while the tires on my old Scout seemed to wear well, I can't speak with any certainty as to the quality... I like Big-O's warranty, but if the E-range A/T's junk, then who cares?

 

[argve]

I don't know how to tell them apart but I'm going to be going over to Discount Tire in the morning and trust me I'll be talking to ol' Americo (yes that's his name) about why these things are crap and what we can do about it. I'm currently about a thousand miles from my first rotation schedule of 6k miles and want to talk with them about this problem. I had not noticed it until we were hitched and on our way last month to Florida. At first I wrote it off as just wind because when we started out the wind was horrible it was blowing everyone around on the road even cars, but once we got out of the wind I noticed that nope her butt was still wagging something bad. So I'll see what Americo has to say... He'll probably look at me and say tough noogies but we'll see who gets to install the other set of tires on her from his response.

 

[The Warden]

Travis, what wound up happening?

BTW, Calvin was right...Big-O didn't exactly laugh at me, but it was pretty close. I figured as much, but i had to try, eh?

I guess at this point, I get to try and find a shop in the Bay Area who knows the front suspension on Ford 4x4's well, make ABSOLUTELY certain that the suspension and steering system are happy, then see if I can sell the tires on my own...

Thank you all again... *sigh*

 

[rthomas]

tim, i dont think id be quick to blame the tires, thats a big trailer for one axle, and my expieriance with single axle has taught me that the truck towing it needs to have some weight in the bed- i use a single axle trailer for my quads (7x10) and it wiggles with 2 bikes on the trailer and an empty truck, however if i have the 8' camper on the truck it feels much better, even with three bikes on the trailer. singles suck and id rather pull a 10k tandem than a 3k single any time

 

[argve]

Travis, what wound up happening?

BTW, Calvin was right...Big-O didn't exactly laugh at me, but it was pretty close. I figured as much, but i had to try, eh?

I guess at this point, I get to try and find a shop in the Bay Area who knows the front suspension on Ford 4x4's well, make ABSOLUTELY certain that the suspension and steering system are happy, then see if I can sell the tires on my own...

Thank you all again... *sigh*

I have not made it down there yet... Got busy doing "honey do" items... Like freaking mulch in the flower beds At least the mulch is free I just have to load it myself.

 

[ibsmurf]

rthomas....your situation makes perfect sense if you think about it. When you put your camper in the bed, the truck weighs a whole lot more, and the added weight is centered right over the rear axle. Adding 2-3000 pounds to the bed makes a whole lot of difference in the stability of the truck, especially when there's a trailer trying to push it around.