1997 2x4 Bumper Change add Tow Hooks

[tedallen]

I am in the process of replacing the original style bumper and lower valance on the subject vehicle with a different lower valance having slots for tow hooks (from what I can tell this valance and tow hooks were only available on 4x4 vehicles).

To my dismay, I noticed that the frame tubes on my vehicle are not pre-drilled for the tow hooks to mount. In fact, the frame tubes are actually different from those of 4x4s. I went back to a salvage yard and noted the differences between the front end of the frame tubes on 2x4 and 4x4 vehicles for the first generation vehicles:

• Bumper mounts are recessed 2.25" from end of frame on 2x4 and 3.25" on 4x4.
• Frame tube of 4x4 vehicles has an overlapping section within the bottom of the tube so that there are two thicknesses of the frame where the holes are drilled. The 2x4 frame tube has very little overlap where the weld joint is made in the bottom of the tube.
• The center of the front hole for the tow hook mounting on 4x4 is approximately 4 5/8" back from the end of the frame tube. This would equate to 3 5/8" from the end of the frame tube on a 2x4 to maintain the same relationship between the face of the bumper mount brackets and the tow hook mount locations.

My concerns are whether or not I would cause integrity issues with the frame rails if I were to go ahead and drill the 11/16" holes required to mount the tow hooks without the frame rails having the overlapping sections to drill through as well as the fact that the tow hooks might not be completely level because of the weld bead in the middle of the bottom of the frame rails where the tow hooks will be mounted.

It seems hard to believe that it could be cost effective to have two different front frame rail designs for 2x4 vs 4x4 vehicles but I guess there are probably more differences further back.

Has anyone else attempted this, and if so, have you experienced any issues?

Thanks,

Ted

 

[alaskanexpy]

if i were you i would go ahead and drill it but add a piece of 2" flat bar steel on the nut side of the frame(inside) to help stiffing it up.

 

[Captain Morgan]

Second that.

Add the plate inside the frame rail as wide as will fit, doesn't need to be a full 1\4" thick.

Have you already bought the tow hooks?


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[tedallen]

Thanks alaskanexpy and Captiain Morgan.

I bought the tow hooks at the same time I got the bumper/valance from Pull-a-Part. They are Ford OEM hooks.

So you both recommend putting a steel plate inside the frame tube between the frame and the OEM plate with the threaded tubes in it for the mounting bolts to thread into? I don't have any welding equipment. Would it be sufficient just to drill holes through both the frame tubes and the steel reinforcement plate to match up with the tow hook and mounting plate holes?

Should I try to get a thin plate on the tow hook side (outside) bottom of the frame tube to make the surface more level for mounting the tow hooks or would that cause alignment issues with the slots in the lower valance?

Thanks,

Ted

 

[Captain Morgan]

YUP - don't make it too complicated.

Just put some plating inside, maybe some JB Weld to help with weight distribution. The same on the bottem where the tow hooks touch the frame rail.

The drilling is the hard part!

You need a couple of hardened bolts and larger flat washers.

Cinch it down.

This should be strong enough to do what they need to and prob not turn left\right when being pulled on at an angle.

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[gaping46and2]

Take pictures when/if you decide to get this done. I'm considering doing this as well.

 

[tedallen]

YUP - don't make it too complicated.

Just put some plating inside, maybe some JB Weld to help with weight distribution. The same on the bottem where the tow hooks touch the frame rail.

The drilling is the hard part!

You need a couple of hardened bolts and larger flat washers.

Cinch it down.

This should be strong enough to do what they need to and prob not turn left\right when being pulled on at an angle.

.

How do you recommend using the JB Weld and how thick of a plate should I use both inside and on the bottom (where the tow hooks touch) of the frame rails? I was thinking of using plates an 1/8" thick on both sides that are long enough to protrude approximately .5" - 1" past the mounting holes on each end and are slightly smaller in width than the inside diameter of the frame rails.

I have the OEM bolts for the tow hooks from the same vehicle I got the bumper/valance and tow hooks from? Wouldn't these bolts be hardened enough to do the job? I was planning on using them with the OEM pre-threaded mounting plates inside the frame rails. I was just wondering if I should do anything to stiffen the frame rails where I will have to drill them.

I wish I had a working drill press to go through the reinforcement plates. It would be nice to get them aligned as close as possible. I bought an old "Total Shop" (I think it is a Korean clone of a Shopsmith) years ago, but it was missing some parts. I don't think everything is there to use it as a drill press, but maybe I'll check it again.

Thanks,

Ted

 

[tedallen]

Take pictures when/if you decide to get this done. I'm considering doing this as well.

Hi gaping46and2. I definitely plan on doing it (maybe before the weekend is over) and will take photos and post them. I just want to get advice from others who may have already done this or similar projects in the past to make sure the end result doesn't compromise the integrity of the frame rails.

I have take some vacation time this coming week as well, so if I don't get it completed this weekend, I should get it done within the next few days.

Thanks,

Ted

 

[Captain Morgan]

I think if you go an inch past the holes with 1\8th you'll be fine. I've installed a couple of Curt receivers and the clips that go inside the frame rail is about that thick but not as wide and long. As for the JB Weld, I would just smather the crap out of the bracket and set it in place, it's not an exact science and doesnt have to look pretty.

You can use a piece of paper and a marker and make a template of the holes that are already on your FR. Take the plates and that template to a machine shop etc and pay someone $20 to have them drill the holes for you. If they give them back to you and the bolts fit loosely then you're half way there.

The factory bolts are fine and should still be long enough for another 1\8th "

As you can see from the photos, the frame rail may not be even on the inside so the JV Weld will help smooth out where the plates will sit.















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[tedallen]

You can use a piece of paper and a marker and make a template of the holes that are already on your FR. Take the plates and that template to a machine shop etc and pay someone $20 to have them drill the holes for you. If they give them back to you and the bolts fit loosely then you're half way there.

The factory bolts are fine and should still be long enough for another 1\8th "

As you can see from the photos, the frame rail may not be even on the inside so the JV Weld will help smooth out where the plates will sit.

The photo you have of the inside of the frame rail looks to me like the ones that were made to accommodate the tow hooks from the factory. It has the overlapping oval sections where the drilled holes go through two layers of the frame rail where it overlaps. My frame rails don't have those large overlapping sections.

I had thought about taking a template to a machine shop that matches the holes in the factory plates that are already drilled and threaded at the correct dimensions and let them drill the plates for me (maybe even have them cut them to size as well. I guess one upside to the "down" economy is they might be more willing to do a small job like this on short notice.

If I use a 1/8" thick piece on both the inside and underside of the frame rail that would be a net increase in thickness of 1/4". I don't think this will be too much for the length of the factory bolts. The 1/8" on the underside shouldn't be an issue for aligning with the slots in the bottom valance either.

Thanks,

Ted