Jump to content

Undercarriage

tinbad
 Share

Recommended Posts

tinbad Enthusiast

tinbad

Posted
Posted

I thought I hit something driving today and decided to check underneath (for the first time.. I know..). Two things got me concerned:

1. There’s seems to be some “bubbling” on the part of the frame(?) could it be they screwed up and painted/coated while moist? Or is this normal?

2. I noted a very distinct checker pattern of rust on 4 corners of the frame (Showing pic of 1 but they’re on all 4 sides in the same location). Looks like something scratched/imprinted from a lift(?)

 

Should I be worried? Needless to say all I’ve done is take it to the dealer for the numerous issues I’ve been having so if anyone is at fault it would be them (or the factory).

 

19 LT TB, 13k miles, only had the truck for 10 months (custom ordered and delivered in July 2019)...

6DFE25CB-3B1F-4DF3-B867-C52C4F8D6ECD.jpeg

2D8DAAA7-DC25-4CCB-9959-BE8914802B1F.jpeg

OnTheReel Senior Enthusiast

OnTheReel

Posted
Posted

Normal. Frames are dipped, so you’ll see some excess runs and bubbles where it collects. Mine has that stuff in the same spot, so did my 2016.

 

Since it’s just a wax coating, it very easily rubs off of the lift points. I touch mine up with the same product the factory used after service, not a big deal if you keep up with it.

 

https://www.daubertchemical.com/store/product-list/corrosion-prevention/nox-rust-x-121b

 

 

 

 

  • Like 2
  • Thanks 2
Z71-Like-A-Cadillac Enthusiast

Z71-Like-A-Cadillac

Posted
Posted
2 hours ago, OnTheReel said:

Normal. Frames are dipped, so you’ll see some excess runs and bubbles where it collects. Mine has that stuff in the same spot, so did my 2016.

 

Since it’s just a wax coating, it very easily rubs off of the lift points. I touch mine up with the same product the factory used after service, not a big deal if you keep up with it.

 

https://www.daubertchemical.com/store/product-list/corrosion-prevention/nox-rust-x-121b

 

 

 

 

How far does a can of that stuff go? I think I'm going to get some. Just trying to decide how much I should buy.

OnTheReel Senior Enthusiast

OnTheReel

Posted
Posted
10 minutes ago, the-wild-moose said:

How far does a can of that stuff go? I think I'm going to get some. Just trying to decide how much I should buy.

It goes a long way for just touching up. I did buy a case because the price break was so big. Split it with a few buddies and still have 2 of the 3 cans I started with like 4 years ago.

tinbad Enthusiast

tinbad

Posted
  • Author
Posted

That’s a relief, thanks. This truck hasn’t been trouble free to say the least and glad I don’t have to add this to list.

 

So just spray the stuff on the rusty parts? I’m also not sure how much of it to get, a can is 15$ but then shipping is too so was thinking to get a case but I likely won’t use it all.

 

 

bdsilverado Enthusiast

bdsilverado

Posted
Posted

Is that lift mark even in the correct spot to lift the trucks up from?  

  • Sad 1
OnTheReel Senior Enthusiast

OnTheReel

Posted
Posted
54 minutes ago, tinbad said:

 

So just spray the stuff on the rusty parts? I’m also not sure how much of it to get, a can is 15$ but then shipping is too so was thinking to get a case but I likely won’t use it all.

 

 

Yes, it can be applied directly to active rust. The company claims it’s very effective at stopping further corrosion, and that’s been my experience. The weakness is anywhere lift pads touch and edges of body mounts where the coating would naturally be thin. I do my best to keep up with those areas here in the rust belt and everything under my truck still looks more or less like new after two winters. 
 

A case is literally a lifetime supply and then some. 

  • Thanks 1
2016 Sierra Owner Senior Enthusiast

2016 Sierra Owner

Posted
Posted
15 hours ago, bdsilverado said:

Is that lift mark even in the correct spot to lift the trucks up from?  

I would say yes. Because the just past the hole in the frame on the far right of the pic. The frame starts to curve upward and the spot circled by the OP is the closest flat spot there is to the front.

 

  • 2 years later...
  • 1 month later...
micew64352 New Member

micew64352

Posted
Posted (edited)

Hello! Based on what you’ve described and the picture you’ve attached, it seems like the bubbling and rust on the frame are not normal occurrences. It’s understandable that you’re concerned, especially since you’ve only had the truck for 10 months and have driven it for only 13k miles.

Since you’ve mentioned that you’ve only taken the truck to the dealer for numerous issues, it’s possible that the fault could be on them or the factory. It’s best to bring your truck to the dealer as soon as possible so they can properly inspect and address the issues.

 

 

Edited by txab
  • Haha 1
redwngr Senior Enthusiast

redwngr

Posted
Posted
On 4/6/2023 at 4:04 AM, micew64352 said:

Hello! Based on what you’ve described and the picture you’ve attached, it seems like the bubbling and rust on the frame are not normal occurrences. It’s understandable that you’re concerned, especially since you’ve only had the truck for 10 months and have driven it for only 13k miles.

Since you’ve mentioned that you’ve only taken the truck to the dealer for numerous issues, it’s possible that the fault could be on them or the factory. It’s best to bring your truck to the dealer as soon as possible so they can properly inspect and address the issues.

 

 

OP's second picture -- the one that was called 'bubbling' is absolutely normal.

Frames are hung by the front end and washed then dipped in a tank containing the waxy frame coating. 

Those 'bubbles' are thicker coating that didn't run/drain/drip off. 

 

That part of the crossmember would have been the 'bottom side' of the crossmember when it came out of the dip tank.

 

 

 

 

  • Thanks 1
Gangly Senior Enthusiast

Gangly

Posted
Posted (edited)

That's not bubbling, those are droplets where excess coating material has collected without dripping off.  If you see that, you know you have sufficient coating there, its a good thing to see.  The marks on your frame are from lift pads on a vehicle lift.  Your vehicle got put on a lift and that's where the lift forks contacted the frame, completely normal to see surface rust here.  if you are nervous, purchase a few cans of Daubert Nox, it's expensive but it's what the manufacturer uses as a coating at the factory.  I have used it multiple times as touchup and it works VERY well.

Edited by Gangly
  • Like 1
  • Thanks 1
NE18 Enthusiast

NE18

Posted
Posted

I always sand down IL6. Then I’ll use a rust inhibitor spray paint then the wax. 

Gangly Senior Enthusiast

Gangly

Posted
Posted
On 4/8/2023 at 11:25 AM, Interleukin6 said:

Before applying Daubert Nox, should I sand down surface rust or can it be used on top of rust?

I never sand down the surface because I don't want to go through any coatings/protectants on the metal surface.  If rust is present, I wipe the area clean of the coating, apply a rust remover/dissolver, let it sit then rinse it off, dry it, apply a layer of protective paint, then spray the Daubert coating.  If there is no rust or just very minor surface rust, I wipe the surface rust off to get it as clean as possible, and spray the Daubert NOx directly onto the surface and move on.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.3k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    342,716
    Total Members
    8,960
    Most Online
    BDS my HD
    Newest Member
    BDS my HD
    Joined

  • Who's Online   0 Members, 1 Anonymous, 459 Guests (See full list)

    • There are no registered users currently online

  • Latest Articles

  • Posts

    • BDS my HD
      Brand new to this forum. Questions about re-gearing my 26’ HD

      By BDS my HD · Posted

      Hello hello looking forward to expanding my knowledge of the 2026 2500 HD that I just bought.   Truck has 3500 miles on it four-wheel-drive crew cab and I’m about to put a 6 1/2 inch BDS lift on it 18 x 10 -25 offset with 37’s   Already have the wheels and tires just waiting on the lift install in about three weeks   Question what surprises am I not gonna be happy with?  I’m not new to lifted trucks so I know that acceleration towing gas mileage all that is affected..   Question is those of you that have this truck this powertrain with a 10 speed Allison and have done the mods that I’m doing,,, how bad is it? Is that Allison constantly gonna be hunting for the right gear to go into? And what about towing, acceleration, fuel consumption as mentioned?    Lastly how come I can’t find any ring pinion gear set up for these axles and when could I expect to see them?   I apologize if there’s any typos I’m doing speech to text on my iPhone.    
    • linc45bn
      2013 2500HD 6.0L intermittent no crank no start

      By linc45bn · Posted

      I've got a 2013 2500 6.0L Flexfuel. Drove the truck earlier today with no issues. Went to run an errand tonight and noticed key fob wouldn't work. Figured battery was dead, so replaced fob batter. Still wasn't working. Grabbed my other set of keys with the other fob and that one wasn't working either. So I manually unlock truck and insert key. Interior lights come on, dashboard lights up, turn key and truck starts. Turn truck off, like a moron, and try starting again. This time no crank, no click, no nothing. Lights still come on and dash lights up, but now I'm getting a service 4wheel drive, service tire monitor, etc. Check voltage on battery and Im showing 12.2v. Throw my battery charger on it and give it 15 mins and try starting again. But still no crank no start. Decide maybe its a bad battery, run to autozone grab a new one and put it in. Same issue. Disconnect battery and let it sit for 15 mins. Try again and still nothing. I had managed to roll the windows down earlier as its a humid night, but now I can't get them to roll up. Power locks are also not working now. Then randomly I try the key again, and it fires right up. Immediately I roll up the windows as we have nothing but rain forecast this week. I shut it back off wait 30 seconds and start up again. Worked a 2nd time. So turn it off, start putting things back together. Try one more time, and back to no crank no start. And now the car alarm starts going off. Had to disconnect battery and leave it that way for the night as I don't think my neighbors would appreciate my alarm going off again tonight. Any thoughts or help would be appreciated. 
    • Grumpy Bear
      first oil change - 2026 2500HD gas

      By Grumpy Bear · Posted

      No one will care for you like you care for you. Do what you can for as long as you can. IMHO of course. 
    • Grumpy Bear
      Oil Consumption

      By Grumpy Bear · Posted

      How about them NICKS!!! 
    • Peoplemvr
      GMC 1500 Illuminated Front Grill Emblem REPLACEMENT.

      By Peoplemvr · Posted

      Hi there.  Long time lurker, first post.    i have read the previous posts regarding the water ingress problem with this emblem.  I bought my 1500 SLT the  summer of 2025 new and after reading the MANY problems with these emblems failing I decided to install one anyways.  As per a YouTube video, I sealed ( or tried to) this sign with silicone sealant around the outer perimeter joint and the holes that were already somewhat sealed on the rear plate of the emblem.  And installed the connector assembly using dielectric grease on the connectors. The installation looked great and worked well for about 4 months……then FAILURE.  Grrrrrr…… I live in the great white north and wash my truck weekly in an automatic car wash  to keep the salt off.  Let me tell you that removing the old, failed emblem is a whole different animal than removing the OEM individual letters without removing the grill assembly. Mainly because the illuminated logo is built differently than the original letters which  you can remove the red surface lettering with a knife or some kind of blade which gives access to the tabs which hold the logo onto the grill. So I had to essentially destroyed the old emblem to remove it. Doing so killed my chance of doing somekind of autopsy on the failed , old logo.  But there was plenty of water inside when I ripped it apart.  Prior to installing the new assembly I tried it with the old harness and it works fine.   Does anyone have any insight as to where the water is getting into this emblem? I intend to seal the new logo with slow curing epoxy this time around using a syringe.  I think this newer emblem may be an updated unit which I hope GM got the vendor to fix. It has an October 2025 date on it.    If this one  fails,  I am just going to revert back to the non-illuminated letters….AFTER PULLING THE GRILL.    Any thoughts on sealing with epoxy would be appreciated. Thx!   Doug  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...