Truck Bed Trailer Project

[Ravenkeeper]

I'm looking at starting a full-size (preferably Chevy) long bed pickup trailer project. I have found and looked at a few older trailers for cheap, to start with. I am looking for some help from all of you experienced builders.

- Should I use the truck's chassis/frame?
- Should I use a military or other trailer frame?
- Other than weight reduction, are there GVWR benefits for replacing the differential axle with a straight/trailer axle? (I have seen some truck bed trailers out there that were built on boat trailer frames. Very questionable to me.)
- I'm looking at eventually changing out the bed on it to match my 2015 Silverado, can I do this with a Ford or Dodge frame?

My other plans for it include, and are not limited to:
- Installing/Keeping a toolbox/storage bin on the tongue,
- Installing/Keeping the original tailgate and bumper (for that particular year/generation),
- Keeping the gas tank, if still installed, or installing one, for extra fuel for equipment or tow vehicle on long runs (dual tanks would be even better),
- Having working tail lights, side markers (clearance lights), and would like operational reverse lights (although tail lights are a must, side & reverse lights may be added later),
- Looking at keeping the differential/drive axle and attaching electric brakes (eventually/possibly),
- Tow package (for third brake light, bike rack, luggage pod, etc),
- Eventually, but not right off, installing a shell and/or tonneau cover.

I have even toyed with the idea of making a tandem axle version. That would be a unique trailer.

 

[ntsqd]

- Should I use the truck's chassis/frame?

We did, but not a Chevy frame, an IH frame. Need to watch out for frames that drop under the cab as they can result in too low of the coupler. It sort of did on ours.

- Should I use a military or other trailer frame?

Could, depends on what you need the trailer to do.

- Other than weight reduction, are there GVWR benefits for replacing the differential axle with a straight/trailer axle? (I have seen some truck bed trailers out there that were built on boat trailer frames. Very questionable to me.)

Parasitic loss is the biggest reason that I would remove the OEM axle. C-Clip axles would also drive the removal of the stock axle. Electric trailer brakes may or may not be adaptable to an OEM axle, I would suspect not.
On ours we cut the ends off an old, square spline D60 housing and shoved the spindles into a tube making a tube axle that uses the D60 wheel hubs, bearings, & spindles. Added a fill & drain plug to the tube so now the wheel bearings run in about 3 gallons of 90wt.

- I'm looking at eventually changing out the bed on it to match my 2015 Silverado, can I do this with a Ford or Dodge frame?

Anything is possible, desired level of effort involved is the question.

My other plans for it include, and are not limited to:
- Installing/Keeping a toolbox/storage bin on the tongue,

We keep all of stuff needed to tow it in a tongue box.

- Keeping the gas tank, if still installed, or installing one, for extra fuel for equipment or tow vehicle on long runs (dual tanks would be even better),

We thought about doing this, reality is that the trailer has only been used on a trip where that function might be nice/needed twice.

- Having working tail lights, side markers (clearance lights), and would like operational reverse lights (although tail lights are a must, side & reverse lights may be added later),
- Looking at keeping the differential/drive axle and attaching electric brakes (eventually/possibly),
- Tow package (for third brake light, bike rack, luggage pod, etc),

Sched 80 pipe rear bumper incorporates a socket receiver hitch just for that sort of thing. Note spare on an S-10 spare tire winch.

Loaded with my grandfather's tools:

 

[Ravenkeeper]

- Should I use the truck's chassis/frame?

We did, but not a Chevy frame, an IH frame. Need to watch out for frames that drop under the cab as they can result in too low of the coupler. It sort of did on ours.

- Should I use a military or other trailer frame?

Could, depends on what you need the trailer to do.

- Other than weight reduction, are there GVWR benefits for replacing the differential axle with a straight/trailer axle? (I have seen some truck bed trailers out there that were built on boat trailer frames. Very questionable to me.)

Parasitic loss is the biggest reason that I would remove the OEM axle. C-Clip axles would also drive the removal of the stock axle. Electric trailer brakes may or may not be adaptable to an OEM axle, I would suspect not.
On ours we cut the ends off an old, square spline D60 housing and shoved the spindles into a tube making a tube axle that uses the D60 wheel hubs, bearings, & spindles. Added a fill & drain plug to the tube so now the wheel bearings run in about 3 gallons of 90wt.

- I'm looking at eventually changing out the bed on it to match my 2015 Silverado, can I do this with a Ford or Dodge frame?

Anything is possible, desired level of effort involved is the question.

My other plans for it include, and are not limited to:
- Installing/Keeping a toolbox/storage bin on the tongue,

We keep all of stuff needed to tow it in a tongue box.

- Keeping the gas tank, if still installed, or installing one, for extra fuel for equipment or tow vehicle on long runs (dual tanks would be even better),

We thought about doing this, reality is that the trailer has only been used on a trip where that function might be nice/needed twice.

- Having working tail lights, side markers (clearance lights), and would like operational reverse lights (although tail lights are a must, side & reverse lights may be added later),
- Looking at keeping the differential/drive axle and attaching electric brakes (eventually/possibly),
- Tow package (for third brake light, bike rack, luggage pod, etc),

Sched 80 pipe rear bumper incorporates a socket receiver hitch just for that sort of thing. Note spare on an S-10 spare tire winch.

Loaded with my grandfather's tools:

So, not all frames droop?

For the most part, it will be used for hauling whatever. Every couple years, I have a ton of. Sage brush to get rid of.

As for the electric brake, I've seen it were someone installed a brake rotor to the driveshaft stub and install a device over it.

The gas tank(s) would come in handy should we use it to travel cross country, but not a necessity.

Glad you mentioned the spare tire, that's another idea I would like to keep.

 

[Ravenkeeper]

- Should I use the truck's chassis/frame?

We did, but not a Chevy frame, an IH frame. Need to watch out for frames that drop under the cab as they can result in too low of the coupler. It sort of did on ours.

So, not all frames droop? I'm looking at trying to have the trailer look like my truck and sit at the same level.

- Should I use a military or other trailer frame?

Could, depends on what you need the trailer to do.

For the most part, it will be used for hauling whatever. Every couple years, I have a ton of sage brush to get rid of. My wife & MIL are just about constantly swapping furniture and other crap and I'm fed up with renting trailers.

- Other than weight reduction, are there GVWR benefits for replacing the differential axle with a straight/trailer axle? (I have seen some truck bed trailers out there that were built on boat trailer frames. Very questionable to me.)

Parasitic loss is the biggest reason that I would remove the OEM axle. C-Clip axles would also drive the removal of the stock axle. Electric trailer brakes may or may not be adaptable to an OEM axle, I would suspect not.
On ours we cut the ends off an old, square spline D60 housing and shoved the spindles into a tube making a tube axle that uses the D60 wheel hubs, bearings, & spindles. Added a fill & drain plug to the tube so now the wheel bearings run in about 3 gallons of 90wt.

As for the electric brake, I've seen it were someone installed a brake rotor to the driveshaft stub and install a device over it. BUT, since I'm not looking at hauling a lot of heavy loads, may change for a trailer axle with electric brakes already on it.

- I'm looking at eventually changing out the bed on it to match my 2015 Silverado, can I do this with a Ford or Dodge frame?

Anything is possible, desired level of effort involved is the question.

Guess what I am looking for is, is there a bolt pattern difference between the makes? IE, if I were to buy a cheap truck bed trailer (say I found a Dodge truck bed trailer for $100), and someone was selling their 2015 Silverado long bed for $400, can I replace the Dodge bed with the Silverado bed?

My other plans for it include, and are not limited to:
- Installing/Keeping a toolbox/storage bin on the tongue,

We keep all of stuff needed to tow it in a tongue box.

I may even throw a small generator and/or a couple RV batteries in the box for camping.

- Keeping the gas tank, if still installed, or installing one, for extra fuel for equipment or tow vehicle on long runs (dual tanks would be even better),

We thought about doing this, reality is that the trailer has only been used on a trip where that function might be nice/needed twice.

The gas tank(s) would come in handy should we use it to travel cross country, but not a necessity.

- Having working tail lights, side markers (clearance lights), and would like operational reverse lights (although tail lights are a must, side & reverse lights may be added later),
- Looking at keeping the differential/drive axle and attaching electric brakes (eventually/possibly),
- Tow package (for third brake light, bike rack, luggage pod/rack, etc),

Sched 80 pipe rear bumper incorporates a socket receiver hitch just for that sort of thing. Note spare on an S-10 spare tire winch.

Glad you mentioned the spare tire, that's another idea I would like to keep, or incorporate back into it.

Loaded with my grandfather's tools:

 

[ntsqd]

The Chevy bed didn't fit the IH frame until we made it fit. Suspect that this will be true no matter the mixture of frames and beds is. Even different generations of the same Mfg. probably don't interchange.

AFAIK all pick-up frames droop, but where they droop is the important part. Normal std height is for the top of the trailer hitch ball to be 18" off the ground. When shopping for frames you'll need to keep in mind what height your hitch is going to be and what you'd need to do with any particular frame to get the coupler to that height.

I liked using the Dana 60 full-float hubs and wheel bearings, and I'd do it again in a heartbeat, but I see no real value in using a whole truck rear axle for a trailer axle. I hear guys talk about interchangeability and having a spare diff along, but be real, I've never, ever heard of anyone ever taking the diff out of their trailer to fix their truck. Its one of those fantasies that sounds wonderful and just is not very realistic. Not to mention the added drag it creates in the trailer. Lock your front hubs & go for a drive to feel what the drag of a unloaded but driven diff feels like.

Give some thought to the tongue jack or stand. Most eventually get bent from someone forgetting to wind them up far enough, and then catching them on something. The best design I've ever seen for a tongue jack is on the tongue of the U-Haul car hauler trailers. Next trailer I build or modify is getting one of those.