Rivet question for Sub Roof Rack

[bronzeback]

Hi all. I've been lurking for a while and now I have a question. I have a 90 Suburban and was in the pick a part yard last week. I found a custom made roof rack, with a custom made ladder that attaches to the left rear barn door. The rack spans the entire roof. Front to back, and side to side, so it's heavy. For $20 I couldn't pass this up. It was pulled off a 91 and it was attached using rivets. There are three "feet" on each side for attaching it to the roof and each "foot" is set to have four rivets.

Here are my questions. Are all rivets equal? Any I should or shouldn't use? What all will I need to put them in? Any other pertinent info? It seems like a stupid question and from what I've seen online it looks pretty straight forward but with the weight of the rack itself (let alone when it's loaded) I want to make sure it is secured properly. Any thoughts on what to put between the roof and mounts, around the rivet heads and around the mount bases to help prevent water leaking in? Previous owner just used silicone and I'm wondering if there's something better.

Thanks for any input.

 

[Martyn]

I would install the rack using a threaded insert rather than a rivet.

You can get inserts with O rings that seal the insert against water entry. Then it's just a matter of bolting the rack in place.

If you do decide to use a rivet then I think I'd go with a stainless steel blind rivet.

 

[96discoXD]

I too would stay away from most rivets, especially if you're going to carry much of a load up there. In my experience they just simply aren't secure enough. My ladder rack on my ARE DCU topper is all rivited aluminum and I'm going to redo it all with stainless steel bolts to replace the rivets since I'm going to mount a cargo rack, tools, and hi-lift jack up there.

 

[ntsqd]

The roofs of this generation Sub have a substantial beam not far under them at the outer-most edges. The roof is close to or is sitting on this structure below the outer crease in the roof panel. You can see it if you drop a headliner panel. Advise trying to attach through to roof to this structure rather than just the roof panel itself. Below is my semi-quick rack for a trip to Baja. It was held on with 3 #10 SS sheet metal screws per 'foot'. I walked on it frequently & will be cutting it down to fit the FJ60 with gutter mounts at some point.

 

[bronzeback]

Thanks for the replies. Def. some things to think about. Heres what I'm working with....

 

[evldave]

Follow ntsqd's advice - if you can, drop the headliner, find the crossbeams, and bolt to that (using something to waterproof the holes)...

If you can't line up the current mounts w/the crossbeams, you can still bolt to the sheetmetal, just use some type of metal 'backing' plate inside to distribute the holding force of the bolts...you can get very large washers from some hardware stores, or even just a separate piece of sheetmetal w/holes cut works (this is what I did on my 88 sub, using 1/8" sheetmetal).

Coming from personal experience, rivets, or rivnuts can pull out over time and can leak. Bolts (with nylon nuts) stick around and work really well if you can get to the backside of the metal.

 

[HighRideBOV]

bronzeback,

Sounds like you've got some good advice on mounting, I just wanted to congratulate you on your find. Awesome rack.

 

[bronzeback]

Thanks HighRide. I explained to the lady working at the counter this was a custom rack with ladder (told her what vehicle it was on) and asked if the price was the same and she said yes. Once I got it off she said she didn't realize it was that one and said she should have charged me more. Then she said just kidding, but I think she was serious. A short time later I told her I would be willing to pay more (I knew I was getting a great deal, didn't want her to get in trouble and I didn't want to have a bad relationship with the co.) and asked how much more but she said don't worry about it.

Yes, good advice. I've never done mods like this and have never needed to use rivets so I thought I should ask those in the know before I mounted it. Even though the donor vehicle showed no signs of roof problems and all the rivets were still solid I didn't think rivets would be the best way to go.

 

[ntsqd]

Just a clarification, the structure that I was referring to runs down the length of the vehicle, not across the width. The space in there tapers towards the outer width of the truck. Much like trying to get into the eves of a Hip roof from the attic.

I used #10 sheet metal screws through the roof and into the beam. Not the cleanest way to do the job, but at 3 of them per landing foot and each one being a pain to install (I seriously thought that I was going to break them off) despite having drilled the correct size holes I didn't have any concern about it. After the first one I seriously contemplated tapping those holes and using machine screws, but I was already too big in hole size for the tap.

I used RTV under the landing feet and under the bolt heads. Again, not the most ideal but it worked for the short time that I had that '79 Sub (my "starter" Sub as it were).