Thanks mosseater, actually I did that the same day I adjusted the brakes. But, I just checked and torqued them from where they were. Meaning, I didn't loosen them and then step torque them. Basically I just checked them. Most were within 5 ft/lbs. of correct torque.
It's an interesting thought though. What if whoever put them on first did not step torque them properly? I once had a Mustang that a Firestone dealer rotated and balanced the tires. As soon as I hit the highway, the thing vibrated like crazy. I got home, jacked up each wheel, loosened the lug nuts and step torqued them properly. Solved the problem. The tech apparently used an impact wrench tightening each one down completely before moving on to the next. Hmmm. I have no reason to believe the lug nuts have been removed since the unit was built at the factory. However, who knows?
2012 Ford F250 Super Duty, SC 4x4 XLT, 6.2L, 3.73 gears
2011 Keystone Sprinter Select 29BH
mosseater wrote: I think John Barca did some testing on this matter and found that trailer drums were not manufactured to the same tolerances at automotive drums. They were not perfectly round nor concentric with the axle centerline. Maybe he'll check in and comment.
Your correct Moss - John is a good friend of mine and he actually ran into this when he was installing the self-adjusting brake kit from Dexter... John bought 4 new drums and even those 4 brand new drums were running out over Dexter's spec... Read John's article below - you would be surprised at Dexter's response - - - or maybe you won't be surprised, considering all the junk the RV industry peddles to us!!!
2000 Ford F-250SD, XLT, 4X4 Off Road, SuperCab
w/ 6.8L (415 C.I.) V-10/3:73LS/4R100
Banks Power Pack w/Trans Command & OttoMind
Sold Trailer - not RV'ing at this point in time
Thanks moss, ladams and john (in absentia), those were excellenct articles. I noticed they were from 2009; obviously the industry has not changed anything. I feel much better about the brakes and the situation at hand. Perhaps after several hundred more miles, the shoes will wear in and conform a bit better to the drum, reducing the "catching" points. Either way, it does sound like I'm worrying more about this than necessary.
They're all that way but it's not because they're warped, it's because the machined surface is not concentric with the studs. Sadly it's just another example of poor workmanship.
Scott, Grace and Wesly
2003 Dodge 3500 4x4, 6 speed Cummins (lightly bombed),
2004 Forest River 25RKS many, many mods.
H0NDA eu2000i
While we're on the subject of brakes. There's also a myth about warped disc brake rotors that's been around since disc brakes were invented. Very unusual is it to ever have a warped disc brake rotor. The culprit is the transfer of material from the hot brake pad to the rotor that causes the problem but the rotor always gets the blame.
Here's a good article on the subject if anyone is interested. http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml
"When these pads reach their effective temperature limit, they will transfer pad material onto the disc face in a random and uneven pattern. It is this "pick up" on the disc face that both causes the thickness variation measured by the technicians and the roughness or vibration under the brakes reported by the drivers."
The author also says "in more than 40 years of professional racing, including the Shelby/Ford GT 40s – one of the most intense brake development programs in history - I have never seen a warped brake disc."
2010 Rockwood Signature Ultra Lite 8315BSS
2003 Chevy Silverado 1/2 Ton Extended Cab
HappyTrails2U2 wrote: While we're on the subject of brakes. There's also a myth about warped disc brake rotors that's been around since disc brakes were invented. Very unusual is it to ever have a warped disc brake rotor. The culprit is the transfer of material from the hot brake pad to the rotor that causes the problem but the rotor always gets the blame.
Here's a good article on the subject if anyone is interested. http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml
"When these pads reach their effective temperature limit, they will transfer pad material onto the disc face in a random and uneven pattern. It is this "pick up" on the disc face that both causes the thickness variation measured by the technicians and the roughness or vibration under the brakes reported by the drivers."
The author also says "in more than 40 years of professional racing, including the Shelby/Ford GT 40s – one of the most intense brake development programs in history - I have never seen a warped brake disc."
I've been in the Auto repair business for almost 40 years and I'll tell you "ROTORS DO WARP"! The author interchanging " Thickness variation" and "Warp" in racing applications. In thickness variation the two surfaces of the rotor are not parallel to each other, when wrapped the surfaces are still parallel but not true to the hub. . If rotors didn't warp, then when turned on a lathe we wouldn't need to remove rotor material to get the surfaces true again. What causes "warp", improper wheel tightening and a rapid heat and cool cycle. Heat a piece of metal to the temperatures break materials reach and drop them in a cold puddle of water and the metal will distort. This is what you do every time you stop from highway speeds in the rain.
To the OP, your drums are out of round. They might have been improperly machined from the factory, dropped before installation, had the lugs overly tightened or been heated and cooled rapidly. Have the drums turned.
2008 Starcraft 185SB Antigua
2005 Ford F150 XLT Supercab 4.6
Interesting topics guys - thanks for the additional info... Interesting comments about disk material transfer...
Regardless of what happens, the end result is the same resulting in having to either turn the rotor(s) or replace them and the pads - which reminds me - have to look at my truck - have a little vibration up front while braking
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