Issue with Rennline Tow Hook mount

[sperkins]

Is anybody using these? They seem like a nice unit- all steel/stainless steel.

I chose the option for my model, which was E19.210 113mm.
There is not enough thread to safely secure these. I get about 1/2-3/4 of a turn before it’s fully seated.
You can see how deep the factory tow hook will seat, based on where the black paint is chipped off.
I think it needs twice the number of threads in order for it to seat properly.
I have a message into Rennline, but haven't heard anything. I will be calling them in the morning.

[F4rmost]

I don't know if it's just the shading on the picture playing tricks with my eyes or I stared too long without blinking, but it almost looks like the threads are wrong. They look tighter.

[sperkins]

Originally Posted by F4rmost

I don't know if it's just the shading on the picture playing tricks with my eyes or I stared too long without blinking, but it almost looks like the threads are wrong. They look tighter.

I see what you mean, but trust me, its the picture. The male threads don't make contact with the female threads until the thick part of the stud bottoms out.

I think i know what the issue is, i just need Rennline to provide a solution. Just thought i'd throw it out here to see if anyone else has had the same issue.

[RalliartRsX]

And why is the stock unit not adequate? A multi piece design just adds more failure points vs the stock one piece cast unit.

I use the stock unit on both the front and rear of my race car and have had to use it once when I ran out of fuel on last lap right across the start finish (long story)

I can get 5 OEM tow hooks for the price of one of these lol

[sperkins]

Originally Posted by RalliartRsX

And why is the stock unit not adequate? A multi piece design just adds more failure points vs the stock one piece cast unit.

I use the stock unit on both the front and rear of my race car and have had to use it once when I ran out of fuel on last lap right across the start finish (long story)

I can get 5 OEM tow hooks for the price of one of these lol

I've replaced the following factory items:
Suspension
Brakes
tires
seat belts
wheel bolts-to studs
exhaust
tune
steering wheel

All of which were "adequate" to begin with, so not sure what your point is.

[RalliartRsX]

Apples to oranges

Brakes and tires and such are to make sure the car is compliant and safety items. Exhaust is subjective for sound or.......catless for performance as an example

A tow hook is none of that....Just purely aesthetics and doesn't serve any benefit apart from "it looks cool".......asspecially when the the stock tow hook is designed by the OEM...... and for an item you will use maybe once in the cars lifetime or multiple times if you keep going 4 off and bin it during trackdays or there abouts.

Not here to argue, but asking why the stock tow hook isn't sufficient??

And if you are having issues with thread design on a item that it's entire premise is based off proper thread engagement for it to "function", then........why is the stock one, which is designed accurately not adequate??

[sperkins]

Originally Posted by RalliartRsX

Apples to oranges

Brakes and tires and such are to make sure the car is compliant and safety items. Exhaust is subjective for sound or.......catless for performance as an example

A tow hook is none of that....Just purely aesthetics and doesn't serve any benefit apart from "it looks cool".......asspecially when the the stock tow hook is designed by the OEM...... and for an item you will use maybe once in the cars lifetime or multiple times if you keep going 4 off and bin it during trackdays or there abouts.

Not here to argue, but asking why the stock tow hook isn't sufficient??

And if you are having issues with thread design on a item that it's entire premise is based off proper thread engagement for it to "function", then........why is the stock one, which is designed accurately not adequate??

The stock tow hooks are 100% adequate. I know that big chunk of protruding steel will do its job if called upon. I've been using both F/R since I started the journey. This is not what my original post is about.

[F4rmost]

Originally Posted by sperkins

I see what you mean, but trust me, its the picture. The male threads don't make contact with the female threads until the thick part of the stud bottoms out.

I think i know what the issue is, i just need Rennline to provide a solution. Just thought i'd throw it out here to see if anyone else has had the same issue.

Ah, I thought as much. It was a long shot, but it was a shot.

Rennline generally makes quality stuff from my understanding so I am surprised by this.

Also, odd thing to say by the previous poster with the stock tow hooks being enough. Yes they're "enough," but with that argument why make any modification if stock could be argued as enough. OP's car, OP's money.

[omgzirra_exe]

did you read their installation guide? lol it literally says this

“Note: Due to strength and vibration concerns, most tow hooks will only thread in a 1/2 turn by hand. If your hook fits like this, make sure it’s threading straight and not cross-threaded, then use a 19 mm socket to slowly turn the screw in. It should go in smoothly with consistent effort until it bottoms out. After the initial install tools won’t be needed. This is intentional—when you compare the threads of your Rennline tow hook to the factory hook, you’ll see a big difference in thread profiles. That’s a key part of the design.”

[sperkins]

Originally Posted by omgzirra_exe

did you read their installation guide? lol it literally says this

“Note: Due to strength and vibration concerns, most tow hooks will only thread in a 1/2 turn by hand. If your hook fits like this, make sure it’s threading straight and not cross-threaded, then use a 19 mm socket to slowly turn the screw in. It should go in smoothly with consistent effort until it bottoms out. After the initial install tools won’t be needed. This is intentional—when you compare the threads of your Rennline tow hook to the factory hook, you’ll see a big difference in thread profiles. That’s a key part of the design.”

I did indeed. The issue is that it is completely bottomed out after the 1/2 turn (on the rear specifically). Torquing it with the 19 doesn’t give the result the instructions imply.
You can sink it in pretty good on the front though.

I went after these because of the all steel construction. The quality met my expectations. Their mounting system is flawed. I spoke to the technician at Rennline, and he agreed the threads are too short. He’s sending out some longer studs