GMT 900 Front Fender Rust

[Snagglefoot]

Here are a few shots showing rust low down on the front drivers side fender of a 2008 3/4 ton Suburban. This is very common in the rust prone Rocky Mountain area. The dirt gets packed into the lower part of the inside of the fender behind the fender liner. Replacement fenders are the easiest solution but run $400 to $500 each delivered. They were cheaper at Rock Auto but Rock wanted $ 1500 to deliver them. All prices are USD equivalent.

Here are a few shots showing the rust ground away revealing the dirt, the dirt that came out, the area cleaned up and the solid metal of the frame sprayed with Eastwood Rust encapsulator.

Looking for ideas. I don’t have welding skills but curious if anyone has worked with pre made patches etc. Note there is a set of running boards bolted to the bottom of the frame. Thanks.

 

[charbaby]

Well, since you don’t have a welder, I have watched a bunch of YouTube videos where the repair was done with a can of window & crack expanding foam…GreatStuff, LOCTITE TITE FOAM or any brand.
https://www.amazon.com/s?k=tough+st...60ebaf&tag=googhydr-20&ref=pd_sl_5m6hbps4v1_e
And watch some videos. I’ve done it and it isn’t too bad!

 

[repairman54]

I just did the front fenders on my '16 Equinox. Knock off Amazon ones. $160 each with free prime delivery. Fitment was good. Not worth the work trying to patch them up when you have to paint anyway.
My rust was from the sound insulation that's in the hinge area top to bottom. It stays wet for days and bottom of it goes all the way down into the dog leg. I cut that insulation pad out of my fleet in my signature. They all had it.

 

[cptbarkey]

Wow, the Canadian - US conversion rate really bites, or at least that number looks large. No local wrecking yards that might have one? Its worth going that route to practice removal and reinstall. I have used car-part.com with success searching junkyards.

 

[Snagglefoot]

The GMT 900’s get picked over pretty fast and considering the last GMT 900 Suburban was a 2013 most of them in the rust area have the same corrosion of the dogleg part of the fender. I may replace the front fenders in the future but for now just want to run some material to complete to dogleg without necessarily bonding to the frame. If I did bond the new piece to the frame for support I guess I could clear it all away with an air chisel prior to putting on a new fender.

 

[Snagglefoot]

I picked up some foam and could bond the loose piece of the dogleg to the frame with the foam, then run some fibreglass from the bottom edge of what’s left of the fender, directly to the frame ( the frame is shown in one of the photos as being painted with black rust encapsulator. )

 

[Gasbuggy]

Is the fender some how different than a regular tahoe/suburban?

 

[Snagglefoot]

Is the fender some how different than a regular tahoe/suburban?

The 1/2 ton and 3/4 ton Suburban’s are identical . I have a 3/4 ton. Parts Hub has a number of GM 1240333-3 for the driver side. The Tahoe has the same number. The pickups have a different number.

The Silverado drivers side fender is GM 12430341-3.

 

[Snagglefoot]

Wow, the Canadian - US conversion rate really bites, or at least that number looks large. No local wrecking yards that might have one? Its worth going that route to practice removal and reinstall. I have used car-part.com with success searching junkyards.

Yep, the Canadian dollar was on par with the US dollar between 2010 to about 2014 but lost strength to about 0.71 when the price of oil moved from over $100 per bbl to less than $60. You can almost say that if you divide the price of oil by 100 you’ll have the value of the Canadian dollar in US dollars. The USA imports about 4 million bbls of oil per day from Canada. Also, trucking across border seems to cost a lot these days.

 

[Snagglefoot]

I’ve outlined what I think is part of the frame near where the bottom of a fender should be. Does anyone have a good photo of what that area looks like with the fender removed on a GMT 900 ( 2007-2013) Suburban or Tahoe. Every video I saw seemed to miss that section. Thanks.

 

[Donald]

Replace the fender or live with it. I would be concerned that any fix involving spray foam might cause areas that have not rusted to now start rusting because the spray foam held in water or salt or dirt.

 

[Snagglefoot]

I put the Burb up on ramps and can see know that the part I painted black is actually part of the fender assembly right where it curves under the truck. I missed this section with my manual applications of Krown rust inhibitor. Here are some shots from underneath. There is a pocket formed where dirt can accumulate. In that pocket is also the sound insulation that reduces road noise. I can’t believe my Burb has that much cruddy metal underneath.

 

[Snagglefoot]

The vertical bolt is where both the fender and the side board is bolted to the frame.

 

[dfarr67]

I oil mine as early as possible- avoids this situation.....

 

[Danno]

Partify.ca, I order prepainted fenders, bumpers etc. quite a bit. Would recommend.

 

[Snagglefoot]

Ok, here are some shots of my Rookie attempt to make my CIA Suburban look great again. I went for the poor boy option. To bridge the gap of missing section I put on a stick-on aluminum screen then stuck it to the metal with Bondo. I had to put the screen on top of the existing metal for the trick to work.

Then I laid 3 layers of fiberglass, then more Bondo. I used a product called USC Icing on top of that and finished with red Bondo Glazing. Then with lots of sanding I got it pretty smooth. It looked like a Palimino. Then 3 coats of primer and 3 coats of rattle can paint and three coats of clear coat.

Here are some shots. No laughter please.

 

[Snagglefoot]

The screen only sticks on lightly so I used Bondo to stick it to the fender on the three sides that still had metal. There was no metal to adhere to on the left.

 

[Snagglefoot]

I didn’t have enough patience to properly feather the top edge. Next time. Here is the final look. Enjoy.

 

[Snagglefoot]

Here is my material selection. Forgot to mention: To support the screen on the left side I applied a way too large blob of Bondo Glass.

 

[Snagglefoot]

Top left to right: Bondo glass, Bondo, Filling primer, paint, clear coat.

Lower level USC Icing, Bondo Glazing.

The Bondo glass, Bondo and USC Icing all require a cream hardner. The Bondo glazing does not.