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mklinger
04-08-2023, 01:42 PM
If you have ever stared at the front of a '70 - '73 Trans Am (like I have) you might come to the conclusion that if you ever had to pull the car up on a flat bed or tow it at the track, the solution would be a bit elusive if you did not want to damage anything (bumpers, spoilers, flares, suspension, yadda yadda) in the process.

Well after some (a lot) of hours thinking about how to do it I arrived at an elegant solution I thought I would share with the forum since the forum has given me great ideas in the past.

So here goes.

This is the tow hook I wanted to use, It's from Rennline, it's stainless, designed for Porsche and other Euro cars and it's not made of Chinesium. This is Rennline's 'Universal' tow hook with a thread pitch is 5/8-11

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The ideal location to attach any tow hook is the frame of the car. On the 2nd gen F-Body this equates to the front subframe. Interestingly the very front of the subframe has 2 unused holes. They are almost 7/8 in diameter.
I can't use a bolt that big. 1/2" is ideal to mount a tow bracket so I fabbed a reducing spacer by drilling out a standard 5/16" washer to 1/2" to take up the slack.

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They fit in there perfectly. Now I need to fabricate a bracket to get me from the frame rail to the only open area on the front of the vehicle, the 1 1/8" tall slot between the bumper and the valance.
Here's what I came up with after a bit of trial and error.

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The bracket is 1/4" steel with a 5/8-11 coupling nut welded to it. The 2 holes are threaded to 1/2-13. This bracket slides into the frame rail and is bolted from the top with 2 bolts and some double thick washers.

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I previously had a ground strap bolted there. I didn't want to redrill/retap that location so that was a little tight to the washer but worked out fine.
After this was bolted in you can now see how 5/8-11 coupling nut through the slot below the bumper and above the valance.

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I love when a plan comes together. Now, in the unlikely event of needing to be pulled onto a flatbed or pulled off a track, we just screw in our tow hook.

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That solved the challenge of the front of the vehicle now onto the back. I have a Rideteck 4-Link and needed a solution for a tow from the back. Other than wrapping a strap around the axle I saw no good way to attach anything to the rear without buggering something up. Rennline just happens to have some tow hooks with a 16.5 mm hole that fits perfectly onto the trailing arm bolts. These could be used for towing as well as trailering.

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Hope this is inspiration for someone. Enjoy.

Motorcitydak
04-08-2023, 10:48 PM
Thanks for posting, I’ve been mentally visiting this problem a few times and haven’t committed to anything yet. Came across the rennline pieces before and they look really good. Like to mentioned, the 5/8 bolt is just a bit bigger than I wanted to use. I actually put in a 1/2-20 insert into my front bumper to run something like this. With the rennline piece, does that cap screws go all the way through the piece then thread into the car? Couldn’t tell without buying one. Do you think a 1/2 inch bolt could replace it with a sleeve to make up the space?

Looking at that picture, it seems like the threaded end is all one machined piece. Looks like it would be possible to turn that end down then cut 1/2-20 threads onto it.

mklinger
04-09-2023, 04:28 AM
The tow hook is somewhat modular. You could easily turn down and re-thread the 5/8-11 to 1/2-13

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79 Camaro
04-09-2023, 01:08 PM
Looks good. But and you knew there was going to be one. LOL.
I would add gussets welded to the 5/8" coupling rod top and bottom.

mklinger
04-09-2023, 01:55 PM
Not sure I'm following. What additional loads are you concerned about that would require gussets? Not opposed to improving the design so help me understand. Thanks.

79 Camaro
04-09-2023, 05:06 PM
As I understand the tow device is screwed into the 5/8" coupling nut welded to the 1/4" bracket. Those two welds are going to take a lot of torque when and if you are being pulled out of the weeds on a track day by an over worked track guy. You might be just fine. Should be just fine at a steady pull onto a trailer.

cpd004
04-10-2023, 01:12 AM
Nice job!

mklinger
04-10-2023, 03:19 AM
As I understand the tow device is screwed into the 5/8" coupling nut welded to the 1/4" bracket. Those two welds are going to take a lot of torque when and if you are being pulled out of the weeds on a track day by an over worked track guy. You might be just fine. Should be just fine at a steady pull onto a trailer.

Gotcha, makes sense.