Upgraded Bumper and Bike Rack

ScottK · 07-14-2021, 04:23 PM

I’ve been trying to figure out how and where to store our bikes while traveling. Front of truck, top of truck, tongue of camper, in the truck, in the camper, or back of the camper Once we decided the back of the camper was the best option, it was time to work out an upgrade to the bumper. Lots of examples of these thin 16 gauge 4"x4" bumpers failing when people attach storage racks and bike racks to them. Especially when they aren't even attached directly to the frame. So much bounce behind a camper compared to a vehicle, due to the distance the rack is from the axle.

First I weighed my tongue with the bike rack test mounted on the factory bumper (and spare tire, which gets moved to the front) and only lost about 200 pounds up front. Moving an 82# tire to the front almost makes it a wash.

I decided on a 4-1/2" x 4-1/2"x 3/16" thick replacement and 3' x 6" x 1/4" plate steel for the frame extensions. See below for how I was able to use standard bumper end caps and still store our sewer hose in the bumper.

I used a plasma cutter to cut out a cradle of sorts to hold the bumper. My thought here was this will support the square shape of the bumper and keep it from racking (twisting) with the weight of the bike rack. I kind of stole the idea from those U-shape aftermarket bumper reinforcement brackets.

I cut slots in the frame header to slide the frame extension through so I could bolt & weld the assembly to the camper frame. The 2 end bolts went through both sides of the rectangular frame. 3 of the bolts were self tapping bolts, and just go though one side. I also welded it in a few spots.

PICTURE 1: Old bumper cut off it's mounts. The 2"x4" stubs that are left are sistered to the 2"x5" frame tubes. I decided to weld the new bumper to those in addition to the frame extensions. They are already there, so why not use them....no harm in a little overkill.

PICTURE 2: The slots cut to accept the frame extension.

PICTURE 3: View of the slot from the inside of the header.

PICTURE 4: Cutting the shape for the frame extensions from 1/4" hot rolled plate steel.

PICTURE 5: Frame extensions clamped in place for a test fit of the bumper.

ScottK · 07-14-2021, 04:26 PM

PICTURE 1: Bumper test fit - looks good

PICTURE 2: A better look of the frame extensions - rounded the corners off & drilled bolt holes.

PICTURE 3: Welded 1/8” x 1-1/2 flat stock inside the 4-1/2” square bumper, made for a perfect fit of my existing bumper end caps. Many way to solve this, but I’m happy with this solution.

PICTURE 4: Welds ground off.

PICTURE 5: Caps test fit.

ScottK · 07-14-2021, 04:31 PM

PICTURE 1: When everything was test fit on the camper, I tacked the frame extension to them bumper and removed the whole assembly for better welding position. I suck at welding in perfect position, so I’m completely hopeless welding upside down. I also have the receivers I will use for the bike rack bolted and welded.

PICTURE 2: Another view

PICTURE 3: Frame extension bolts in place

ScottK · 07-14-2021, 04:33 PM

Two more problems to solve. First, my Kuat NV 2.0 Three bike rack isn’t rated for the back of an RV. So my solution is to give it more support. I dabbed up an additional cradle to support and protect the Kuat hinge mechanism. Worked out great. Second problem…There is no room for the oversized spare tire in the back, if I want to fold up the bike rack, so I fabbed up a spare tire attachment for the tongue. More on that below.

I utilized the previous bike rack that was on the tongue for my spare tire carrier. It’s easily removable and very solid.

ScottK · 07-14-2021, 04:34 PM

The beauty of this setup is the ability to use the bike rack on the truck, once we arrive at our destination. Or remove it completely if we don’t need it for a certain trip. The bumper is so solid now, I plan to fab or maybe buy a cargo rack for the back when we aren’t using the bike rack.

**JohnB** · 07-17-2021, 05:56 PM

Hi Scott,

As usual, your handy work is first rate. Great job.

You have the torsion axle on that camper if I recall right, that helps in this situation as it creates a cushion effect for going over bumps of the bump into the camper frame. The folks with the standard leaf springs, no rubber equalizer, no shocks, the back of the frame really magnifies the bumps and vibration of most any road bump.

You have for sure beefed up the mounting into the main camper frame. And I know you are being cautious on the tongue weight reduction. That is the one thing I will alert, double check that the loaded tongue weight is ideally in the 12% or higher range then the total GVW of the camper. Yes, 10% is the bottom limit, but the lighter the camper, the worse one wrong gear move or empty propane tank can take you under the 10% quick. The 12% or higher buys some breathing room. Your Hensley hitch also helps.

Thanks for sharing, always cool to see your upgrades.

John

ScottK · 07-17-2021, 08:31 PM

Quote:

Originally Posted by JohnB

Hi Scott,

As usual, your handy work is first rate. Great job.

You have the torsion axle on that camper if I recall right, that helps in this situation as it creates a cushion effect for going over bumps of the bump into the camper frame. The folks with the standard leaf springs, no rubber equalizer, no shocks, the back of the frame really magnifies the bumps and vibration of most any road bump.

You have for sure beefed up the mounting into the main camper frame. And I know you are being cautious on the tongue weight reduction. That is the one thing I will alert, double check that the loaded tongue weight is ideally in the 12% or higher range then the total GVW of the camper. Yes, 10% is the bottom limit, but the lighter the camper, the worse one wrong gear move or empty propane tank can take you under the 10% quick. The 12% or higher buys some breathing room. Your Hensley hitch also helps.

Thanks for sharing, always cool to see your upgrades.

John

Thanks John. Just got back from a 3 day camping trip. I was playing with worst case loading after I got home. Black and grey tanks 3/4 full (located toward the back), 1 of 2 propane tanks empty, bikes on, water tank empty (toward the front), tongue weight is still 16% or 900lbs. I don't know the exact weight of the trailer at the time, but a previous visit to the scale has me around 5700# loaded, so I think I was still in that ballpark. I was about 1150 tongue weight, fully loaded, before the bumper bike rack mod which pushed my truck load. But I have a new truck now. F-250. Oh boy...where has this thing been all my towing life!

**JohnB** · 07-17-2021, 09:21 PM

OK, 16% is enough tongue weight.

The F250, so the Blue Oval is now in the garage.

Do you have the 6.2 gasser or the torque monster diesel?

Yes, now you can put stuff in the truck bed and still have capacity to spare.

Glad the trip went well.

John

ScottK · 07-17-2021, 10:01 PM

Quote:

Originally Posted by JohnB

OK, 16% is enough tongue weight.

The F250, so the Blue Oval is now in the garage.

Do you have the 6.2 gasser or the torque monster diesel?

Yes, now you can put stuff in the truck bed and still have capacity to spare.

Glad the trip went well.

John

Yup. Long history of Toyota trucks back to 1997. I chose the new big 7.3 gasser & 10 speed tranny. I was spending enough money and couldn't justify another 10k for the diesel. Based on my first short trip...this will do nicely.

Headed out west next.

**JohnB** · 07-17-2021, 10:26 PM

Quote:

Originally Posted by ScottK

Yup. Long history of Toyota trucks back to 1997. I chose the new big 7.3 gasser & 10 speed tranny. I was spending enough money and couldn't justify another 10k for the diesel. Based on my first short trip...this will do nicely.

Headed out west next.

Wow, you went for the new 7.3 V8 and a 10 speed tranny, talk about an upgrade...

My V10, 6.8L with the 5 speed (4.10 rear axle) still has a lot of pulling left in her. She just has a big drinking problem.

OK, you have to report back on how that new motor does linked to that 10 speed tranny when you go out west. Us with inquiring minds need to know!

ScottK · 07-19-2021, 06:33 AM

Quote:

Originally Posted by JohnB

Wow, you went for the new 7.3 V8 and a 10 speed tranny, talk about an upgrade...

My V10, 6.8L with the 5 speed (4.10 rear axle) still has a lot of pulling left in her. She just has a big drinking problem.

OK, you have to report back on how that new motor does linked to that 10 speed tranny when you go out west. Us with inquiring minds need to know!

I think they all have a drinking problem...more or less.

I'll be sure to report back.