A few weeks ago I purchased a 2005 F150 SuperCrew 4X4 with 106,000 miles. The truck drives great and really looks to have been taken good care of. Recently I have noticed something a bit strange when I’m doing around 60 to 70 MPH on the freeway and I hit a rough bumpy patch on the road. The truck will kind of get squirrely and it feels like the back end is kicking out a bit. It is bad enough that my passenger has commented. This is a patch of road that I have driven many times with my previous 4X4 and have never had a reaction like this. My tires, shocks and suspension look completely stock.

Any thoughts or sugestions?

 

106k on the original shocks would have something to do with it. Also, what kind of tires is on it and what's the PSI?

 

Time for new shocks I'd say.
My 07 was the same way till I put rancho all the way around. Now it's solid

 

All four of my tires are Toyo A/T Open Country size LT285/65r18. They are running about 54PSI. As far as the shocks, I'm only guessing that they are the original shocks. They are not springy or don't seem to be worn out.

 

What load range are those tires? Even load range E's shouldn't be run that high with no load. Try dropping them down to about 45. If they are C's or D's run them even lower - maybe 40.

As I said, at 106k the original shocks are due for replacement.

 

They are Load Range E. I will try dropping them down to 45 PSI. I will also look into the shocks.

Thanks

 

According to the tag on my driver’s door my truck came with LT 275/65R18 tires. That is a bit narrower than the 285 on the truck now. The tag doesn’t mention the Load Range on the factory tires. What Load Range would the original tires have likely been and if different than the E’s, how would that affect the handling?

 

What does the tag recommend for pressure? What does the tag say the maximum tire load is?

 

According to the two tags on and behind the driver’s door the PSI is 40 and the GVWR is 7,200

 

Your description of how the truck reacts to bumps at speed is exactly how my old Ranger behaved when the shocks were worn. As soon as I replaced them the handling was night-and-day different!

 

58 psi in 285/65R18 tires on a F150 and no load?

I guess she was bouncing around!

 

The factory tires were Load Range C. Drop them down to 45 and replace the shocks.