New Montero Sport Owner with a Hum

[cnskate]

Hi,

New Montero Sport owner here. Really impressed with this truck so far, even after replacing the valve gasket and anticipating replacing a leaky cam seal It's a sweet ride with OME medium springs and Tokico shocks, and 19 mpg with roof tent.
Have a hum or vibration noise coming from the left front that is really noticeable at 50-60mph, mainly when my foot is on the gas. Replaced wheel bearing, it's been aligned, new tires, tried rotating tires, greased u-joints, replaced fluids in diffs and transfer case, supposedly all of the suspension parts are tight. Any ideas? Front axle shaft freeplay adjustment? Help!

 

[Toasty]

did you replace the idle bearing in the spindle? It's what the axle shaft rides on, it's B-2012 https://www.autozone.com/drivetrain/axle-spindle-bearing/mitsubishi/montero-sport. It's not uncommon but not terribly common either.

 

[cnskate]

Why no, they didn't . I used a small town tire and alignment shop for this, and they are not used troubleshooting obscure foreign vehicles, bless them. I'll give that a try, thanks so much!

 

[Toasty]

Domestic 4wd vehicles have them too but they are often overlooked, it may not even be your problem. Just something to think look at.

 

[cnskate]

Diagnose with an infrared thermometer or just tear apart and visually inspect?

 

[Toasty]

You could try IR diagnosis or maybe pull the drive flange off and rotate the CV with the tire on the ground and listen/feel for bearing crappiness.

 

[cnskate]

Suspect side is 4-5 degrees hotter after 15 minutes of highway driving. Significant?

 

[Toasty]

It's a really small bearing, test and repeat.