Dually Fender Attachment

[Trucksareforwork]

Here’s a question for any dually gurus.

I’m going to be converting a regular longbed to a dually. Already have some fenders. The truck is a SRW converted to DRW many years ago, and I acquired it without a bed. It’s a 4x4 gmc 3500.

I do not have the fender to bed side anchors, and as I look around; they appear to be “rare.”

What would you guys say to a mounting procedure that includes a few studs for placement, and then panel bonding cement for fixture?

I realize this would be a permanent solution. Any other risks?

 

[Ricko1966]

I'd investigate using 5/16 threaded inserts they come in brass,stainless or carbon steel,or time serts. Epoxy the outside before install,then use 5/16th,studs and washers.

 

[EvilGenius]

I'm not familiar with the factory way of mounting the fender flares, but could you use rivnuts? Would allow you to remove them in the future. This would require some sort of flange on the flare though and I haven't ever looked at one closely to see if there is one.

 

[TotalyHucked]

I certainly would not panel bond them on there. I'd say either through bolt with large washers to spread the load or threaded inserts/large rivenuts/something along those lines and then use some kind of felt or rubber between to isolate them

 

[Trucksareforwork]

I'd investigate using 5/16 threaded inserts they come in brass,stainless or carbon steel,or time serts. Epoxy the outside before install,then use 5/16th,studs and washers.

I really like this idea.

 

[Trucksareforwork]

I'm not familiar with the factory way of mounting the fender flares, but could you use rivnuts? Would allow you to remove them in the future. This would require some sort of flange on the flare though and I haven't ever looked at one closely to see if there is one.

Factory way was a coarse threaded stud that threaded into the bedside. I don’t have a picture handy but they aren’t reproduced that I know of.

I like the insert idea offered above. That would preserve removability and still hold well.

 

[Trucksareforwork]

Here’s what one looks like. From the web.

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[bucket]

Besides the studs needed to install the dually fenders, you also have to do a lot of cutting to the bedsides and there is a filler piece that connects the bedsides to the wheel housings.

 

[Trucksareforwork]

Yes to bucket. I’ve been doing my homework and probably won’t get to the actual project for months or years, but I am aware of the cutting required.

I found these on eBay. They may serve the purpose.

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[legopnuematic]

There was a discussion about dually hardware a while back-
https://www.gmsquarebody.com/threads/dually-guys-need-your-opinions.43967/

Just to add that in for additional information

 

[legopnuematic]

Adding my thoughts, I believe having a “hanger bolt” or stud with the with the flange in the middle is the key to success.

That allows for the stud to bottom out in the flare, so controls the depth, but when installed on the bedside it puts the clamp load between the flange and nut, not the threads going into the flare itself. So the flare side of the studs job is just holding the flare on. Not maintaining a clamp load.

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[Strick]

Those look similar to the studs used on the spoilers and flares on the F-body cars. Makes sense. I have a C&C dually with a flatbed, the dually pickups that I've seen the bed is butchered from the General to make those humps work.

HS

 

[Tonimus]

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This is probably the best view of how they work. My fenders were trashed and I took a sawzall to it before unbolting them. Studs thread into the flare, then the flare gets bolted to the fender. Mounting options depend largely on what flare you are planning on using.

 

[Trucksareforwork]

You must be registered for see images attach

This is probably the best view of how they work. My fenders were trashed and I took a sawzall to it before unbolting them. Studs thread into the flare, then the flare gets bolted to the fender. Mounting options depend largely on what flare you are planning on using.

Can I buy the gap covers from you? Those are like hens teeth too. The piece that bolts over the cut bedside and follows the contour of the wheelhouse.

 

[Tonimus]

That truck was totaled years ago when a mustang made a left turn in front of me. Just happened to have pics archived.