2007 2500hd Classic Subframe Peeling

[Bruce03Silverado]

Anyone else here have issues with their subframe peeling? My 2007 Classic 2500HD subframe in the rear is peeling again! I just had it to the dealer back in May and the paint or whatever they use on the subframe was peeling anf flaking off like crazy. They supposedly cleaned it and repainted it. This morning I noticed it flaking again.

 

I took it back to the dealer (the truck only has 23k miles on it and the peeling has happened again in less than 4k miles) and the service rep told me that GM says it's not a problme but if it happens they gave them a quart of paint they are supposed to put on. He acted like it was no big deal but I'm not driving around a $30k+ truck that has the frame rust showing through the rear wheel well whenever someone looks at it. he said it's a common problem and on some trucks it stcks and others it doesn't. I never had this problem with my 1500 in over 70k miles - anyone else experience this? There is a TSB that I have to do a search on as well.

 

Thanks in advance!

[5Alive]

I have a theory about your frame peeling... especially after you said:

 

I never had this problem with my 1500 in over 70k miles

 

 

Which tells me, unless you have changed locations at the same time you changed trucks, that your driving environment has been the same. So whether the roads you typically drive on are paved with salt or paved with gold, it doesn't matter, since you've had a truck whose frame didn't peel, and now you have a truck whose frame does peel.

 

So what's different?

 

Truck frames never used to be painted. They were COATED, dipped in a gooey wax like substance that gets all over your arms and sleeves when you are working under there. The icky stickiness of this waxy coating fluctuated with temperature... when cold, the outermost surface skins over hard, having the appearance of paint. When hot, there is quite a bit more plasticity to the coating, taking on the persona of grease to which the fine dust of the road adhered.

 

The advantage of the wax coating is that it was ductile enough to flex with the frame, which constantly vibrates at various resonances when jiggling down the road.

 

But there were a lot of complaints from UPFITTERS... the people who take truck chassis and upfit them with service bodies for tradesman, police and fire, delivery and livery, recreational vehicles, etc. At some point around 2006, I recall some OEMs (GM and Ford?) announcing that they were going to start PAINTING the frames instead of wax coating them. I remember reading this move being welcomed by the upfitting industry.

 

But hardened paint is not as flexible, unless it is expensive paint with flex agents in the forumula.

 

My theory is that the OEM's cheaped out on the frame paint... because big rigs have painted frames, and they flex just as much, if not more. That's my theory anyway.

 

Curious to read what the TSB says.

[Bruce03Silverado]

I have a theory about your frame peeling... especially after you said:

 

I never had this problem with my 1500 in over 70k miles

 

 

Which tells me, unless you have changed locations at the same time you changed trucks, that your driving environment has been the same. So whether the roads you typically drive on are paved with salt or paved with gold, it doesn't matter, since you've had a truck whose frame didn't peel, and now you have a truck whose frame does peel.

 

So what's different?

 

Truck frames never used to be painted. They were COATED, dipped in a gooey wax like substance that gets all over your arms and sleeves when you are working under there. The icky stickiness of this waxy coating fluctuated with temperature... when cold, the outermost surface skins over hard, having the appearance of paint. When hot, there is quite a bit more plasticity to the coating, taking on the persona of grease to which the fine dust of the road adhered.

 

The advantage of the wax coating is that it was ductile enough to flex with the frame, which constantly vibrates at various resonances when jiggling down the road.

 

But there were a lot of complaints from UPFITTERS... the people who take truck chassis and upfit them with service bodies for tradesman, police and fire, delivery and livery, recreational vehicles, etc. At some point around 2006, I recall some OEMs (GM and Ford?) announcing that they were going to start PAINTING the frames instead of wax coating them. I remember reading this move being welcomed by the upfitting industry.

 

But hardened paint is not as flexible, unless it is expensive paint with flex agents in the forumula.

 

My theory is that the OEM's cheaped out on the frame paint... because big rigs have painted frames, and they flex just as much, if not more. That's my theory anyway.

 

Curious to read what the TSB says.

 

 

 

No environment change - live in the same place. My 1500 was an 03 and my 07 is the same frame they've been using on the HD's since at least 2000 - even the first NBS 2007 2500HD's were built on the same subframe as mine. The frame is flaking just as if it was old paint on an old wood house - flaking off in small chunks and you can see rust underneath. There's no way a 3/4 ton truck or any truck for that matter should have issues with flaking like that - not when the sides of frame never see the road. It's not flaking off underneath but on the side of the frame as you look in the wheel well and with the size of the 2500HD frame it's quite obvious when you look. Maybe not a big deal to GM or a problem when the issue is hidden under the truck but when you look at the side of the truck and can easily see it then there is a problem. I'm not going to drive around in a truck that all you see is a rusted subframe on both sides in the rear wheel well. The dealer is telling me it's a common problem and it wouldn't matter to me as much if it wasn't so obvious when you look at the side of the truck. Out of sight out of mind sorta thing but you can't miss it and everytime I wash the truck it's noticeable - heck I can't even hit the frame with a light spray of water w/o some more flaking occuring. It shouldn't come off that easy regardless of what it is.

[RonJ]

I think I'd go to Advanced Auto Parts and buy a couple cans of Undercoating spray, and then forget about it...or try to.

[ursandal]

While it isn't satisfactory that the paint is peeling, I'd highly recommend you get some Por-15 rust prevenative paint and coat the area yourself. Por15 is extremely hard and is best put on when there is lite rust on the metal. I've used it in the past on old jeep frames and it's never failed me.

 

Al

[Bruce03Silverado]

I understand what you guys are saying, but my point is that I paid $30k for a HD truck that can't even keep a coating on the subframe and this truck was designed to be worked hard? I don't use my truck nearly as hard as it was designed for but I'd hate to think what the frame would look like if I did use it the way it was meant to. I didn't pay that kind of money to have to run out to the store and buy my own undercoating. Old vehicles trying to restore - yes I can see that - but a barnd new HD truck with 23k miles on it?

 

BTW, the dealer said GM provided them with the undercoating spray and that's what they used that is now peeling off - again.

 

Apparently some of the newer trucks are having the same problem as well.

[59ih340]

For some reason they seem to be taking a step back to '70's when they rusted like crazy. My front bumper had holes rotted through at 65k. I have been using Eastwoods hd antirust on my frame every spring. It's the closest i've found to being like the original finish...But I completely see and agree with your point. it's a lot of money to spend on a "project" vehicle from the factory.

[chrisb1]

See post below

[chrisb1]

With my 2008 GMC 2500HD DURA, I had LINEX shoot the bed and they used an aspalt based undercoat for under the truck. They shot below the bed, inside all fenders and

all but the actual frame rails which are wax coated from the factory.

 

So far, no chipping, pealing, etc.

 

I would have the underneath presure washed to remove flaking paint and get someone like LINEX to undercoat the truck. I paid $420 for the bed and $150 for the bottom of the truck. I know it is not cheap, but you will never have to have the dealer redo the work or turn to spraycans.

[Mighty HD]

My 07 classic had the same problem.

 

I just fixed it with undercoating from a body shop.

[Bruce03Silverado]

I know the General Sales Manager at the dealer (he works out at the gym at the same time I do in the a.m.) so I called him. I had him look at the truck at the gym and he agreed it shouldn't be doing that and that it looked bad especially since I just had it done less than 4k miles ago. He told me to call him at the dealer later in the day. I did and he called up the street from the dealer and tomorrow after the oil change and tire rotation they are taking it and having it undercoated and paying for it so I won't have the issue again. Nice way to keep your customer service and satisfaction high!