Cutting frame on a bob

[dilligaf13]

Alright, it's time to fire up the torch to chop the frame and complete my bob. My question is I'm looking on How Much Do I Cut Off?

and it shows them cutting the frame 11 1/2 inches forward of the end of the bed to account for the bumperettes. I want to add a hitch when I'm done so I need all the frame I can get. Does anyone know of any issues with only cutting the frame a couple of inches short of the back of the bed and sliding the bumperretes, pintle, and rear cross member inside the extra frame? Doesn't appear to cause any issues but I figured I'd ask to avoid cutting the frame twice. Thanks.

 

[Recovry4x4]

No hard and fast rule with these moods Dan. Consider that the bumperettes on the factory frame bump out to be a little wider if I recall correctly. Another consideration is whether or not you want to be able to drop your tailgate straight down.

 

[MrM4]

Get out the tape and start measuring, when I cut mine ( dont rember the exact numbers or I would share) I figured for the rear bumperettes and I made sure my Tail gate would hang strait, Kinda wish I had removed the bumperettes and just went with lights and hooks on the back. I have no intentions of ever pulling a trailer though.

 

[mikew]

Those measurements work well with a Curt 15530 hitch. The picture shows a truck with that hitch installed. The receiver sticks out a fair bit from the back edge of the mount, so it's pretty close to even with the end of the bumperettes.

 

[booger]

It seems like I cut 30" off of my frame...no bumperettes and the tail gate will hang straight down

 

[MO MV man]

I cut mine the same amount I cut the bed: 36"

The bumperettes lined up just like they did stock.
I merely removed the whole rear crossmember and slid it inside the frame after shortening.

 

[Awesome Possum]

My bob was made longer, maybe 10". I found that when I went to mount the rear member (with the pintle), the diagonal supports interfered with the rear spring mount bolts. Ended up that I had to go with the frame being a couple of inches longer, and the bed not being able to swing down, but I did want to be able to pull trailers. I also figured out that the bumperettes are a big part of the structural integrity of the rear of the truck. If I were going to leave them off, I'd at least use some angle iron as outside gussets on the back corners. I'm no engineer, but that feels right to me.

 

[dilligaf13]

I cut mine the same amount I cut the bed: 36"

The bumperettes lined up just like they did stock.
I merely removed the whole rear crossmember and slid it inside the frame after shortening.

That's exactly what I was looking to do. Thanks for the help.

 

[dilligaf13]

My bob was made longer, maybe 10". I found that when I went to mount the rear member (with the pintle), the diagonal supports interfered with the rear spring mount bolts. Ended up that I had to go with the frame being a couple of inches longer, and the bed not being able to swing down, but I did want to be able to pull trailers. I also figured out that the bumperettes are a big part of the structural integrity of the rear of the truck. If I were going to leave them off, I'd at least use some angle iron as outside gussets on the back corners. I'm no engineer, but that feels right to me.

That's was my next concern. I wasn't sure if the pintle support bracket would squeeze in with a little modification or if I need to fabricate a new on. Thanks.

 

[ranchhopper]

I took 34 inches off the frame on all the trucks I bobbed but its all relavent to where your spring hangars are mounted on the frame. All the trucks I did I ground the rear two of the three rivits off that hold the crossmember to the frame behind the cab. After grinding the heads off these would be on the bottom flange of the frame I slid the spring hangers up against the head of the remaining rivit when bolting the hangers on the bolts go through the same place the rivits came out of. Doing it this way I had the same standard for all of them same size driveshaft etc but like I say it all depends where your rear axle is as to how much you cut off the back.

 

[DUG]

You should PM 100Dollarman (aka Mark aka Hundy). IIRC he has bobbed a truck or two before.

 

[juddspaintballs]

I cut my frame exactly 36" shorter from the rear and I also cut a 36" section of bed out of the middle and welded the two parts back together. 36" out of the stock bed makes the stake pockets line up with the proper spacing so you literally just lost one section of bed and it keeps everything looking stock-like. The stock bumperettes and rear crossmember slides back into the frame where you cut it off and bolts up just fine (USE GRADE 8 BOLTS). The pintle hitch is perfectly functional just like stock.

If you wanted a standard receiver hitch, check out this hitch:
http://www.steelsoldiers.com/deuce-modification-hot-rodding/46506-deuce-removeable-hitch.html

I'm in the process of welding the quick release tabs onto my frame now. Spring hanger location doesn't make a difference with this hitch and the price was amazing.

 

[Tinwoodsman]

I cut 36" from my frame and stock bed. I wanted to be like Judd

 

[Seth_O]

I cut 36" from my frame and stock bed. I wanted to be like Judd

Tin - you may want to check your rear x-member. It looks upside down. I didn't realize the pintle wasn't centered vertically until after I had the whole thing reassembled and the bed on it and found I had some interference between the top of the pintle and a support on the bed .

It could be the angle of the pic, but much easier to flip it now than once the bed is on......

 

[dilligaf13]

That's something l'll definately pay attention to. According to my measurements I may have to trim the bottom of the pintle support bracket thereby losing the bottom two bolt holes in order to clear the spring bolts. Once I confirm I'll add some pictures.

 

[Tinwoodsman]

Thanks Seth. You have ruined my week but all is not lost. I installed my bed months ago and there is no clearance problem between the open hook and the bed frame. I will probably leave it as is because you are right. It would be a real task to change now.

TWM

 

[Seth_O]

Thanks Seth. You have ruined my week but all is not lost. I installed my bed months ago and there is no clearance problem between the open hook and the bed frame. I will probably leave it as is because you are right. It would be a real task to change now.

TWM

Sorry man - I have been able to get mine to work the few times I've needed the pintle. It's been functional enough I haven't worked up the determination to tear the whole thing apart and redo it.

Some day, when I don't have more critical projects - and I have more time than chores. Sigh......