Be careful if you flip your RV axles

[rweis]

I wanted more ground clearance. Had the axles flipped about a year ago.



Camped last weekend. Pulled out of the RV site, tested the brakes. One of the spring seats weld (on the axle) totally spun off (drivers side, rear axle), caused the axle to rotate, passenger side spring seat held, sheared the spring retainer bolt and dropped spring leaves out. Passenger side axle end swung toward the rear about 20*.



All happened at 2 mph, total distance about 12 inches.



If this had been on the interstate it would have been fatal for someone. The 2nd axle would have gone into thepath of the vehicle behind me. My 5er would have had 1 axle instead of 2, and become grossly overloaded on that 1 axle and it probably would have failed.



What would have happed to the 5er? Who knows?



If the 5er would have flipped over on its side, would it have taken the truck over with it? How strong is the 5er hitch pin? Would it have sheared?



Just a word of warning. Not a good experience at 2 mph much less 60 mph.



Bob Weis

 

[RustyJC]

Bob,



I'm having trouble envisioning this. Even with the axles flipped, don't the U-bolts go UNDER the axle with the threaded ends passing through a spring plate ABOVE the springs? If so, the spring perches welded onto the axle should be sandwiched in compression between the axle and spring by the tensile loading of the U-bolts. Yes, conceivably the axle might be able to break loose from the spring perches and rotate (although if the U-bolts are tight, that's hard to imagine), but the axle should still have been retained by the U-bolts.



Help me out here.



Rusty

 

[Gary - K7GLD]

YUP, I can't quite picture that either - both the perch AND the U-bolts share holding duties - the perch itself is possibly the MINOR element in the equation, as long as the U-bolts are properly tight.



ALSO, must not have been a very good welder that remounted the perches - you'd hafta totally DESTROY my axles to get mine to rotate or fall off.



But, these ARE the sort of things that need checking at the beginning of the towing season - I like to get under our 5er, jack up each wheel, and check for odd noises from the wheel bearings or brakes.



Thanks for the heads-up!

 

[rweis]

The drivers side:



The U bolts retained the axle package spring perch and all. That side the spring perch weld broke and the axle rotated with the spring perch remaining in place about 160*, but that side the package retained position.



The passenger side:



The spring perch did not move. The spring center bolt sheared. The spring has 6 leaves. The 3 longest top leaves shifted aft about 1" per leaf #2 and #3. The top 3 leaves have a keeper clamp around them which kept them from seperating like the lower 3 springs that did seperate. The bottom 3 leaves departed now leaving a gap of about 1". The top plate the U bolts are in shifts aft to the extreme aft end of the spring. The U bolts that are normally perpendicular are now angled toward the aft ground at about 30* (because of the aft shift and the now 1" more gap with the 3 smaller spring leaves missing) and the only thing keeping the axle on the 5er at all is the U bolt plate that has shifted aft to the maximum extent of the rear spring hanger and instead of being parallel to the ground is at a 30* angle (front plate end angled down rear plate end angled up). The U bolt that normally has 6 leaves now only has 3 leaves.



Aftermath:



Because we were camping with our camping group and we have one designated person that watches each rig depart to watch for anything wrong and he signaled me to stop is why I only went 12".



The park we were at has a major RV service facility at it. They got a LARGE forklift and raised the frame with the seperated spring package, we used a comealong to get the axles somewhat aligned, (remember the drivers side axle is still in the correct placement front to rear, the axle rotated on that side) chained them together, and I pulled forward about 20' into a camp site.



Now, I see the problems are:



Alignment of the axles, welding the spring seat correctly (actually I want a new axle with the seat welded on top from Dexter), is there any dammage to the spring set from overstressing?



The springs are Dexter D80 with slipper springs (8000#).



Since we were going slow the bearing package should be ok?



The tires on that axle may have to be replaced due to the scuffing (flattening) of a portion of the tread.



The front axle spring seats will have to be checked and rewelded (same guy welded all four spring seats)



Any other ideas?



Bob Weis

 

[Mark_Kendrick]

The brake hubs bolt on to the ends of the axle. unless you have oil bath axles(usually 10,000+# Duals ) they shouldn't have needed to weld anything. They just take them off and flip them over. Reroute the brake wiring and you're off. I think the brake hub is on a symmetrical bolt pattern so you could even flip the brake hub. I am assuming they are electric brakes.



Sounds like poor workmanship to me. Not a problem with the axles themselves unless it was the factory weld that failed.

 

[RustyJC]

The brake hubs bolt on to the ends of the axle. unless you have oil bath axles(usually 10,000+# Duals ) they shouldn't have needed to weld anything. They just take them off and flip them over.

The term "flipping axles" is a misnomer. These axles have camber built into them, so it's essential that their orientation doesn't change when the axle is relocated from above to below the springs. The axles are not flipped (i. e. , turned 180 degrees). The spring perches are added to the top of the relocated axle (as Bob indicated), but the brake hubs would not have to be removed and inverted since their position relative to the axle would not change.



Rusty

 

[Grunt]

I know of a guy that insisted on "flipping" his axles instead of doing a "spring over". Took him two sets of tires to go from North Idaho to Phoenix , needless to say he did it right the second time :-laf

 

[Motofreak]

Thanks for the heads up, I did mine last year. Guess I will check u-bolt tension.

 

[K5IP]

A good weld is necessary because when the brakes are applied, all the rotational torque from braking is present at the perch. Herein lies the problem.

Make sure you have a good weld on the perches on the other axel. Some folks welding these things do not understand that the perch not only holds the axel but also absorbs all the braking torque.

Rog

 

[mpwalker]

Sorry to hear about your problem, know others that have had problems after doing the same thing, then others with none. On the pin to hitch question, sorry to say we have seen 3 or 4 5ivers on their side along the side of the interstates with the TV still hooked and locked, so think most good hitches are going to stay hooked from what we can tell, which means the truck is going over with the trailer, do not know if that is a good thing or a bad thing.

 

[mikel]

Just a point to consider, I run a Reese 18k hitch. My truck does not weigh anywhere near 18k, so I would expect the truck and trailer to stay together "for better or for worse".



Mike

 

[Eric_77]

My dad had his pick-up flip over while the trailer stayed upright,strnage weird set of circumstances bumper pull trailer with surge brakes the trailer just pushed the truck and it jacked knifed flipping the truck. Then all the semis I see flipped over on their side doing abrupt turns or during wind storms I would say without question truck will go if trailer goes in a fifth wheel connection.

 

[rweis]

Finally got the 5er to a repair facility.



Bottom line:



The axle, spring perch, springs, spring centering bolt, large U bolt keepers are a package. It is IMPERATIVE that ALL aspects are perfect. Spring perch welded SOUNDLY on ALL sides and the weld penetrates the axle tube and the spring perch, the springs are not overloaded, the centering bolt is keeping it all aligned, the U bolt keepers are CHECKED for tightness regularly.



Where we can effect this is we check the U bolts for tightness. I do not know a torque value, but "tight as you can physically pull the breaker bar" is a good area to be in. The U bolt tightness holds the WHOLE package together.



In my case we found the drivers side spring seat weld was superficial at best. Why it let go now is anybody's guess. When the axle rotated the spring perch on the passender side held, sheared the centering bolt and some of the smaller leaves in the spring package seperated. Upon today's inspection this action even bent the axle tube out of round which severly compromises its integrity and strength. New axle tube on order ($1400 tube + $300 freight (Dexter D80 with EZ Lube)), their expense.



A basic premise this whole event brings up, do not take the axle flip decision lightly. You are depending on EXPERT welding, CAREFUL alignment, YOU keeping a check on the U bolt tightness (actually you should check yours periodically regardless).



We tend to be complacent about the RV running gear. I have learned more about the RV suspension / spring assembly than I ever thought I would know. COULD have been a disaster, but was not.



Thanks again for all your inputs.



Bob Weis

 

[KBennett]

Good post!

I "flipped" my axles on my old 1970 Terry TT last year. It has solid square axles and square U-bolts so spinning it would have to really snap something else first.

After I flipped it we made a trip and before the next trip I checked everything and found one of the U-bolts had loosened. It looked like one of the lock washers split and worked it's way out because it was MIA.

It's always a good idea to crawl under and make sure everthing is in order.

 

[jkalchik]

Bob, personally, I *WOULD* find out how much torque those u-bolts require. The u-bolts on my modified Jeep only take 55-60 ft. /lbs. , and I find it quite easy to stretch them. And every time I get them loose, they get checked after a day.



A friend of mine a few years ago had just completed an axle swap on his Jeep before a trip to Moab. He wheeled for a day and a half before the axle shifted, he'd only tacked the perches in place. The axle pinion rotated up 45 degrees or so.



Seriously, this is a good warning to *ALWAYS* re-check everything after suspension work, whether on a trailer or a vehicle.

 

[Gary - K7GLD]

After buying the '02 2500 we now have to pull our fiver, I needed to swap the axles down under the springs to gain clearance over the truck side rails - but since my axles - and whole trailer ('88 model) were old and had lots of miles, the brakes and bearings all needed attention as well. And since the whole axle assemblies needed to be removed anyway to remount to the springs, I chose to simply replace the ENTIRE axles, including all brakes, drums and bearings. I ordered replacement Hayes assemblies from South Western Wheel in Texas, and the cost at that time INCLUDING shipping, was cheaper than rebuilding the Dexter setup the trailer came equipped with - and after the swap, my brakes were FAR superior to what the Dexter's provided.



Total cost for my entire swap - me doing all the labor, was under $500 - very worthwhile, since I now have all NEW running gear, and great brakes!

 

[jwduke]

Good post!

I "flipped" my axles on my old 1970 Terry TT last year. It has solid square axles and square U-bolts so spinning it would have to really snap something else first.

After I flipped it we made a trip and before the next trip I checked everything and found one of the U-bolts had loosened. It looked like one of the lock washers split and worked it's way out because it was MIA.

It's always a good idea to crawl under and make sure everthing is in order.

Don't really know if this would have anything to do with your u-bolts loosing up or not, but a guy who works on suspensions for a living told me, to never ever, reuse u-bolts & nuts in a suspension system.



Reason being, u-bolts are made out of twist steel. They are made to go one way. When they are installed (new) they are tightend up, and the twist steel, is made to twist in the same direction as they are tightened, so this keeps pressure on them to stay tightened.



My thaught is, if they are unbolted, they loose this twist steel feature.



As cheap as u-bolts are, and custom made ones are easy to find, this should be a consideration in any axle flip on a rv trailer.

 

[wtfd6]

im glad to have read this since my 5er needs to be raised 12" just to sit on my truck. will take some planning to do this modification. thanks, mark

 

[magaliasram]

I had the axles flipped on my old 88 Shasta 29. 5 Fifth Wheel. The shop that did the axle did an excellent job. But the factory weld on the drivers side rear spring shackle was more of a tack weld than a good penetrating weld. The long and short of it I backed into a campsite and as I backed up on some planks to level out the spring shackle snapped loose from the frame. I had to call in a guy with a portable welder from 40 miles out and have him weld the shackle back on the frame of the trailer. I had him also check the rest of the shackles and he found one other with a weak weld so he rewelded that one also. Here is the best part, after 1. 5 hours work and a 40 mile trip to get to me on a Saturday it only cost me $75. 00. I was then a happy camper.

 

[Southbound]

Flipped Axles

Hello Bob!



Sorry to hear of your misfortune with the flipped axles. I had the same thing happen to my axles when pulling out of an RV park and applying the brakes. Basically the dealership who welded the axles did a very half a## job and because of it I could have had serious damage done to my vehicle and trailer had I been on the interstate. Glad it happened when it did. Solution: Due to the damage of the axles and the leaf springs I had to order new axles... . so I ordered a larger diameter axle from Dexter with the "saddle plates" welded on top of the axles... ... which was done in the factory. By having a larger diameter axle it allowed me to have larger saddle plates with larger U-Bolts. Issue: If you order too large of an axle then you will have to switch the hubs which will in turn reguire you to change out your wheels to fit the larger lug pattern of the new hub. With the increased diameter axle it will also effect the ride of the trailer based upon the weight ratio of the trailer to axle. In my case I upgraded from a 2 inch axle to a 2 1/2 inch axle which was a moderate change. I also increased the tire size of the stock trailer wheel to give me added lift to my fith wheel. Sounds like you got your problems fixed but I wanted to chime in and let you know that your arent alone. For those of you out there who are thinking of lifting your trailer be very careful because these dealerships out there are NOT welders by trade!!! Just my . 02



Southbound