Matching my 5er Height to my Pickup

[bobinyelm]

I recently solicited suggestions on how best to raise my Wildcat 24RL to match the height of my 2WD Dually Dodge truck, and got many helpful suggestions.

I am reporting back after deciding how to do it, and how it worked out in case others may encounter the problem. No way was anything I did unconventional or revolutionary, but in a way, that's why I am posting, so others will feel comfortable following the cookie-cutter steps. It truly WAS so easy a cave man could do it, though it would have been nice if the components had been commercially available.

"Modern" 5th wheel RVs seem to be higher than older ones to begin with because truck rails are higher than they used to be, but my 2008 Wildcat was still too low to get me the minimum of 6" rail clearance with my stock 2003 truck.

I needed roughly 1.5" to tow level with 6" rail clearance (which was above the truck's tail lights since the 2wd dually truck naturally sits nose low vs. the 4wd dually that sits level).

I searched everywhere for factory-made lift blocks, but ALL were too wide for my 5er's 1 3/4" wide leaf springs. Checking w/ RV dealers revealed that many had either done lift-mods themselves, or had farmed it out for customers to whom they'd sold 5th wheels, and none indicated any problems reported by customers later. They all said a 1 1/2" lift should have zero effect on the stability of the trailer based on their experiences.

I sourced new U-Bolts from a local racing supply shop for my 3" diameter axles that were coincidentally 1 1/2" longer than my stock ones. That was the easy part, and at $5 each was cheap.

I was hoping to find 1 3/4" rectangular steel tubing w/ 3/16" wall thickness to build my spacers, but the closest I could come was 1 1/2" (square) w/ 1/8" wall thickness, which I thought to be minimal. I paid the steel supply shop to cut me 4-4" lengths (since their cut-off saw was better than mine), so the cost for steel was about $10 total, including the tubing and strapping for the end caps. I cut lengths of 1 1/4" X 1/8" steel strapping to fit tightly inside the 1 1/2" tubing, and welded the pieces recessed 1/4" inside the tubing to reinforce my spacers.

I called around, but no one knew the size pins and holds I'd need to use for the spring-pack bolts that served to hold the leaves together and locate the axles on the springs, so I dropped one axle and measured. I was surprised that it was 5/8" (all of the RV dealers thought it was 3/8" or 1/2").

To accommodate this, I drilled 5/8" holes through the tubing top-to-bottom to make sure alignment was maintained, then cut cheap Grade 3 5/8" bolts (4 cost me under $2) down to length so 1/2" of the unthreaded portion projected from the hex-head to engage the holes in the axle spring pads. I inserted the bolts from the inside out in the tubing and welded the heads to the tubing inside to secure them before installing the recessed end-caps.

Here are before-and-after photos to show how the job came out. In retrospect, I would have made the spacers a bit longer than the 4" pads on the axles, only so the narrower-than-spring spacers couldn't rotate past the U-Bolts if they got loose (low probability). After I run these a few thousand miles, I may tack-weld the ends of the spacers to the axle spring-pads. This would secure them while making it easy to grind-off the welds should I ever want to return my trailer to stock height.

Overall, installation was an absolute breeze. I was afraid that the axles might shift when dropped and make one-man installation difficult, but it was really easy, with it taking only 15 minutes per axle-side to install the parts once I had my trailer raised (w/ 1/4" tire-to-ground clearance to remove the wheels).

The pictures of the lift blocks aren't "beautiful" as I was too lazy to get my MIG gas bottle re-filled, so just stick-welded the items, and didn't stress much about getting all of the weld spatter and slag off the welds. Maybe next time...

Before


Lift Blocks


After

[tworootless]

Looks like something I would have done. I would have welded the two perches together. Nice job. . .

[TXiceman]

If they are pinned, I would not worry about welding the two blocks.

Ken

[JIMNLIN]

The idea is old and not a accepted method of raising a mulitaxle trailer from a safety standpoint. Trailer suspension side scrubb their tires going around cornors. This adds stress to the suspension U bolts. Now throw in suspension block and the stress on the U bolts/spring keepers/top plate increases.
Thats one big reason their not offered commercially. Nor is it offered OEM or a option from a axle or trailer manufacture.
I have personell experince with suspenson blocks on a tandam axle Gn flatdeck trailer even after my trailer manufacture said not to. I found out the hard way he was correct.

[bobinyelm]

How high did you lift it, and what was the weight? I imagine you're talking 2 axles?

What let go?

[RVluvin]

Thats how the hot rodders and low riders use to do it. Should it fail, be sure and let us know, because that how I would have done it.

[bobinyelm]

Quote:

Originally Posted by RVluvin Thats how the hot rodders and low riders use to do it. Should it fail, be sure and let us know, because that how I would have done it.

I absolutely WILL report back.

For a conservatively driven car, or a single-axle trailer I have confidence that lift blocks are just fine, but I do understand that they magnify spring wrap-up under torque or heavy braking, and in multi-axle trailers other effects as well.

I am eager to hear if JIMNLIN's bad experience was with a modest lift like 1.5" with a relatively light RV (compared to some of the heavy iron out there), and if it was, and caused catastrophic damage, I will likely pull my spacers and call it a day.

I've asked him to tell us about the failure that sounds like it was pretty dramatic and traumatic, so I am sure he will report in.

[wingnut60]

If he was referring to a GN flatdeck, I would assume that he was dealing with quite a lot more sprung weight than your trailer. Your job looks fine and I would not think the extra height will cause you a problem.
Joe

[Ray,IN]

That is practically identical to how my 5er was raised. The work was performed by the large truck repair shop in Chamberlain, SD. They said they lost count of how many recreational trailers and work trailers they had modified this way. Our 5er pulls much easier now too.

[bobinyelm]

That's reassuring, Thanks.

I hooked up the 5er today and we used it for local driving errands and shopping (about 60mi overall), and it felt just like before.

I listened for any unusual noises from the suspension or the tires, and kept an eye on the tires in the rear-view mirror.

I rechecked the U-Bolt torque when we got home, and everything was still snug.

Just building confidence. We will do several more such trips before we take it on a trip. The warning about catastrophic suspension failure really spooked my wife, but after today she relaxed a bit. When I ran over an empty plastic pop bottle in a parking lot she was convinced we had something fail (until I showed her the pop bottle).

Thanks for the comments.

[JIMNLIN]

What difference does my experience make with your decission to use suspension blocks on a trailer. If your satified with what your doing go for it. Axle manufactures and trailer manufactures would be a better source of advise for suspenion mods that a RV website.

My experience came from my installing a 2" thick HRS block welded to the saddle on a loaded 12k flatdeck trailer. The longer U bolt /top plate twisted allowing the spring keepers to open and that allowed the leaves to seperate on hard turns which finally broke the U bolt on one end of the axle. That allowed that end of the axle to swing back under the rear axles. Luckily it happend on a hard turn getting out on a secondary state highway.

A truck and auto spring shop near me repairs all size of trailer from lawn mower trailers up to semi trailers. They only add suspension blocks to a trailer if the owner signs a disclaimer. They've been in business since '68.

I hope your blocks works better for you than others I've seen. Keep a close watch on loose/broken/twisted U bolts and make sure the leaf spring keepers are doing their job.

[bobinyelm]

Quote:

Originally Posted by JIMNLIN What difference does my experience make with your decission to use suspension blocks on a trailer. If your satified with what your doing go for it. Axle manufactures and trailer manufactures would be a better source of advise for suspenion mods that a RV website. Your experience tells me what to keep my eyes open for if my trailer exhibits the same failure mode that yours did, which is not totally improbable. Rarely (though not always) do things suddenly break all-at-once. They tend to show signs of impending failure long before "the final straw breaks the camel's back." I've been a licensed aircraft mechanic and FAA maintenance inspector for 36 years, and based on the experience of the high-time aircraft of any type, certain trouble-prone areas of specific aircraft are scrutinized for similar failures through more frequent inspections. When signs of impending failure are first noted, remedial action is taken to prevent damage propagation to where catastrophic failure may result. You'd be AMAZED at how many commercial jet aircraft are flying around with serious wing-cracks that were found early, and properly repaired/reinforced based on either findings of such impending failures or actual failures involving catastrophic failure and loss-of-life in similar airplanes. This is not the stuff the public is made aware of, of course, unless it is exposed by some spectacular accident that steals the headlines. My experience came from my installing a 2" thick HRS block welded to the saddle on a loaded 12k flatdeck trailer. The longer U bolt /top plate twisted allowing the spring keepers to open and that allowed the leaves to seperate on hard turns which finally broke the U bolt on one end of the axle. That allowed that end of the axle to swing back under the rear axles. Luckily it happend on a hard turn getting out on a secondary state highway. Not sure what "HRS" means, but it would be interesting, though unknowable, to know whether that one turn started and finished the damage, or if there was growing evidence of stretching/bending of the U-Bolt preceded the breakage that went unnoticed because the area was out-of-view. But to answer your question, based on your warning, I know better what to look for, and what to avoid if I can (i.e., very sharp turns on pavement). I already try not to turn sharply on pavement where tires have full friction with the road, but I also know at times, you do what you have to do. Dirt, grass, or sand on pavement allow tire slippage, and probably stress the suspension much less on such turns. Though it will not prevent what happened to you, I will obtain a set of four extra U-Bolts and a couple top-plates, and carry them with me, as well as carrying the original U-Bolts, which would hopefully allow me to restore the OEM suspension on-the-road where replacement parts might be hard to come by. A truck and auto spring shop near me repairs all size of trailer from lawn mower trailers up to semi trailers. They only add suspension blocks to a trailer if the owner signs a disclaimer. They've been in business since '68. I hope your blocks works better for you than others I've seen. Keep a close watch on loose/broken/twisted U bolts and make sure the leaf spring keepers are doing their job. I will, thank-you. I will make a habit of including them in my daily walk-around before-driving inspection, or if I have to make a really sharp turn on pavement. Knowing what let-go will also help me prepare by carrying some replacement parts with me that might mitigate the result. I appreciate your sharing your experience, and though it may appear I have disregarded your advice, you have made me more aware of the consequences. Others appear to have had good luck with modest "lifts," but in case I am not so fortunate, being ready for the likely failure mode because of your counsel is quite valuable. Thank-you for sharing!

***

[JIMNLIN]

HRS = hot rolled steel.

This particular trailer was in commercial service. Lots of full turns on a daily basis in loading yards and worksites.

You might think about a U bolt/top plate up grade. One poster went to the next size in diameter U bolts and a thicker top plate for much more clamp pressure on 2" blocks. He also added heavier spring keepers. All per a truck spring shop recommendation.

[Franka548]

Bobinyelm,

It looks like you did a really nice job on your spacers, the only thing that I see that could cause you some grief down the road is the grade 3 bolts that you used, all center bolts are grade 8. The grade 3 could wear letting things move around, I'm not saying they will, just that they could, everything else looks great, I wouild not be afraid to put them on my 5er, and it weighs just shy of 16,000#. Keep an eye on your ubolt torque, and if they start loosening, you know that you have stretching going on and will need to replace them. Again, nice job.

Frank