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Sub frame addition

terryaGJ
Explorer
Explorer
Bought a new truck which is over 3" taller than my old one, so I'm getting ready to have a 4" sub frame added to my 2010 Keystone Cougar with 11,000 miles towing on it, to get it level. At the very least I'll have new spring bushings installed. Any recommendations on what else would be good to do while it's all torn apart? Any concerns about going 4" higher on the trailer? Should end up ~13' overall hgt so that shouldn't be a problem. Thanks.
18 REPLIES 18

Blazing_Zippers
Explorer II
Explorer II
We had a 3 inch lift done by a company in our area. The existing shackles were cut off completely and large rails were welded along the trailer frame that extended well past the place where the shackles were attached. Two more rails were welded across the between the new rails forming a box frame for strength. Then the stock shackle arraignment was welded back on and the axles reattached. The cost was a little over $1100.00. The work is the strongest thing on the trailer!

ol_Bombero-JC
Explorer
Explorer
Old-Biscuit wrote:
Cut the spring shackles off
Weld 2" x 4" tube onto frame
Weld shackles back onto subframe with bracing and side to side lateral support tubing

Install WET bolt/bronze bushing set




Unfortunately the "image" doesn't show up.

Try a search in the archives. A few years ago a poster had lots of xln't pics of the mods OB is talking about.
(Maybe "image" are those pics).

And, of course, Biscuit is referring to *square* tube.

:W

Ralph_Cramden
Explorer II
Explorer II
terryaGJ wrote:
I'm scheduled to get my subframe addition done in another 10 days. I'll be going with new shackles and wet bolts (Mor/Ryde kit), a new Equaflex equilizer to replace the old one, plus three cross members across the hangers. Thanks everyone for all the feed back, it really helped me and I appreciate it.

Terry


Good Luck.

Just make sure your guy knows his welding, and that working with the cheap, thin, low grade steel Lippert uses on these frames takes a little finesse while welding. Adding gussets and other reinforcement in critical areas is also good idea. Possibly, hopefully, your frame is not Lippert. Back around 2010 Keystone was using Dexter frames on a lot of models, until Lippert bought out Dexter's frame division
Too many geezers, self appointed moderators, experts, and disappearing posts for me. Enjoy. How many times can the same thing be rehashed over and over?

terryaGJ
Explorer
Explorer
I'm scheduled to get my subframe addition done in another 10 days. I'll be going with new shackles and wet bolts (Mor/Ryde kit), a new Equaflex equilizer to replace the old one, plus three cross members across the hangers. Thanks everyone for all the feed back, it really helped me and I appreciate it.

Terry

laknox
Nomad
Nomad
Terry, every wet bolt kit I've seen includes heavy replacement shackles, so don't spend extra on shackles separately.

Lyle
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Nv_Guy
Explorer III
Explorer III
Probably ought to have to some bracing done between the lower I beam flange and the web, as the load on the bottom flange will be more due to 4" spacer.

SDcampowneroper
Explorer
Explorer
Definitely weld the x members directly between the hangers as low as possible. C channel iron is best as its top & bottom flange are the strength you need and can be positioned to encircle the hanger bolt head.
The wag the dog effect is the cause of frame failures, particularly on I beam frames. I welded for a living for 28 years, Have fixed a few, always the cause was insufficient X members.

terryaGJ
Explorer
Explorer
Thanks everyone for the feed back! Looks like I'll do three cross members, install heavier duty shackles, and go with wet bolts/bronze bushings.

It looks like it might be better to weld cross members directly into the hangers rather than welding them directly to the frame (like the MorRyde X factor system)??? If that's the case then would have to use channel beam rather than a box beam. Would it really be better to use channel beams between the hangers or use box beams welded between the new sub frame?

Cummins12V98
Explorer III
Explorer III
"Weld shackles back onto subframe with bracing and side to side lateral support tubing"

The side to side support is a BIGGIE!
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blofgren
Explorer
Explorer
Old-Biscuit wrote:
Only 2 across supports?

What about center shackle for equalizer??

Should do that also ....lateral/twisting forces when maneuvering


Exactly. I had to have my trailer frame reinforced this year with more crossmembers and there are 3 of them across each set of shackles. The material used was heavy wall 4"x2" structural steel tube.
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goducks10
Explorer
Explorer
No need to buy a shock kit. Just have the welder guy weld some upper brackets on, then buy some U-bolt spring plates that have the angled edges with holes in them.
You'll need to measure and buy the right length shocks of course. No need for all the $$$ Joy Rider stuff.

2naEagle
Explorer
Explorer
Look at the MORryde website

Wet Bolt & HD Shackle upgrade kit
Brace, Brace, Brace front back and center.
Look at the equalizer at MORryde and pick one you like.
Shock's would be really good. I put Joy Rider on mine. You can find less expensive kit's. Lippert and Dexter make some.
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alexleblanc
Explorer
Explorer
have you though about installing shorter rear lift blocks on the rear of your truck? I just did that to mine and its still 2" higher out back instead of 3.5" and it leveled out my setup without needing modifications to the 5er.
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Old-Biscuit
Explorer III
Explorer III
Only 2 across supports?

What about center shackle for equalizer??

Should do that also ....lateral/twisting forces when maneuvering
Is it time for your medication or mine?


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