Frame flex?

  • HTML tutorial

RadoOverland

Rank 0

Contributor I

30
Marion, OH, USA
First Name
Matt
Last Name
Long
Never Noticed it before but while my truck is flexed on an obstacle, I noticed my door doesn't open or close correct. Is this normal for an 03 silverado or any vehicle at full flex? I dont normally do this sort of thing but was feeling in the mood to flex my very unflexable rig haha
 

Attachments

  • Like
Reactions: Broke

Boostpowered

Rank VI

Member III

4,879
Hunt county, TX, USA
First Name
Justin
Last Name
Davis
Member #

14684

Alot of vehicles will do this, though its the bed flexing opposite the body normally. May want to check the body to frame mounts and bushings the bolts holding the body on may be loose or the bushings shot causing this. Are both doors doing it? Also since your up north you'll want to look for corrosion everywhere, if things aren't corroded loose or worn out you can look at cross braces to reduce the frame flex.

If its just hanging up a little id say it is normal but if you can't close or open it at all then no not normal
 

ThundahBeagle

Rank V

Advocate I

1,548
Massachusetts
First Name
Andrew
Last Name
Beagle
Member #

0

By all means check your body mounts and corrosion. Having agreed with that, the flex will be more pronounced if the mounts are intact and the frame is flexing.

If the frame is flexing and the body is well attached, then the body will also flex. This is why it is often difficult to open vehicle doors after a serious crash. I would be more concerned if your frame was flexing and the body stood still, as that might indicate the body was detached

Although, too much body flex will lead to sheet metal stress and paint chipping away.
 

Billiebob

Rank V
Launch Member

Member III

2,835
earth
First Name
Bill
Last Name
William
Member #

18893

17 years old might be part of the problem especially if there are rust issues.

Frame flex is absolutely normal and a few vehicles are actually built to accomodate that, but not most main stream half tons. Wranglers, Rubicons, the JT, the PowerWagon are all designed to flex. I have a ladder rack with a front bumper extension, I am amazed how much twist my TJR gets off road.

Heres a normal pic of frame flex and the reason most overland bodies use a 3 point mount.
Chassis flex is part of the design.

IMG_3652-1500x1000.jpg

I'll have get a video of it twisting with the ladders loaded this summer.

DSC_0021.jpeg

I used to drive a grain truck and the rule crossing field was always approach ditches, swales, crest hills square on, never diagonally or you would break the frame or suspension. We were always overloaded.

But I'd say your issue of a binding door is age and corrosion related.
 
Last edited:

Boostpowered

Rank VI

Member III

4,879
Hunt county, TX, USA
First Name
Justin
Last Name
Davis
Member #

14684

From the op pics it looks like the driver side bed is moved over a little, but on the passenger side it looks straight thats a little strange considering the position of the truck if those are pics of the same flex. Thats what makes me think a mount is gone could even be a bed mount gone letting the bed push into the cab idk thats a hard one.
Doors being hard to close or open though on a truck chassis is not exactly normal no matter how your flexed Since the cab, frame and bed are separate and isolated, on like a grand Cherokee or some other uni body suv or something doing that while flexing would be more acceptable in my book.
 

Boostpowered

Rank VI

Member III

4,879
Hunt county, TX, USA
First Name
Justin
Last Name
Davis
Member #

14684

I Still question how hard are they to open? Just a little rubbing feel when closing or opening would absolutely be normal, hard to close or open then we got a issue.

Another thing to check that came to mind is the door hinges if they are loose or rusted out it can make doors act funky too.
 

RadoOverland

Rank 0

Contributor I

30
Marion, OH, USA
First Name
Matt
Last Name
Long
Thanks for the replies. The door just rubs a bit while I was like that. Can still open and close just not allighlned like normal. I Never really opened my doors before while flexed. I had body mounts replaced 4 years ago. The frame is solid aside from the very rear crossmember going. Not sure if shes worth throwing money at at this point anyhow. Ive been doing minimal upgrades like bilstein 5100 shocks and a level. But I'm really debating getting rid of her. 335,000 on the clock. Bought her 7 years ago with 67,000.
 
  • Like
Reactions: Broke

Boostpowered

Rank VI

Member III

4,879
Hunt county, TX, USA
First Name
Justin
Last Name
Davis
Member #

14684

Its normal then I wouldnt worry about it, tundra, tacoma or any other pickup truck is likely to do the same when flexing. All trucks ive had or been in to my recollection had a little bit of rub on the door jambs when flexed.
You'll only notice it when you get out to take pics or do spotting, winching, etc.
 

MidOH

Rank IV

Off-Road Ranger I

1,298
Mid Ohio
First Name
John
Last Name
Clark
Ham/GMRS Callsign
YourHighness
Normal.

Standing on the deck of an ore carrying ship and watching the bow FLEX 10 feet is an experience. There's a reason why cruise ship always have a turn that keeps the hallways short now:
 

ThundahBeagle

Rank V

Advocate I

1,548
Massachusetts
First Name
Andrew
Last Name
Beagle
Member #

0

Kind of like that old video of the Tacoma bridge we had to watch in Physics class.

...but that didnt end well for the bridge
 
  • Like
Reactions: Broke

Pathfinder I

1,685
Pacific Northwest
First Name
Steve
Last Name
Claggett
Service Branch
U. S. Army
Full size trucks, longer WB have flex, even my mid size has some flex. It's normal to a certain point but it can become excessive if you old and hard cab/bed mounts.
 
  • Like
Reactions: Broke