nykademus

2007 F150 FX4 - 5.4L - just shy of 80k miles


First off, its cold here -10F air temp, and worse today.

Yesterday I was going back to work from lunch. Stepped on the gas in the parking lot and heard what I later found out is probably the IWE losing a little vacuum and grinding. (my truck has the new style solenoid so it should not be water)

Leaving work, I put it in 4x4 thinking to avoid the grinding noise. The truck did not want to roll when I touched the gas and made a terrible squeal when it did start moving and stopped making noise pretty quickly. I cycled 2 wheel and 4 wheel a couple times and it did not come back. I left it out of 4 wheel drive and was gentle while accelerating, the grind did happen a couple times, lightly, until the truck warmed up and then it was gone completely.

I also stopped and checked the trans fluid, smells fine, is clear, and full.

Got home, checked for heat on the calipers/rotors... all mildly warm to the touch.

This morning, -23F

I left it in 2 wheel drive and baby'd the gas again. It did not squeal but I could tell its laboring a little to get rolling. On the way to work, I could hear a slight hum (hwy speed) and then when I came to first stop (20 miles), I could smell that something is hot. It did not smell like brakes, or engine oil. Maybe gear oil? Not sure.

Did not have time to check for heat upon getting to work, and I was not dressed for troubleshooting in sub zero temps.

I have never had a smell associated with a bad hub, other than a brake smell when real hot. So I'm not sure there.
My concern is possible transfer case issue?

I could really use, and would greatly appreciate someone else's thoughts and/or insights.

Thank you!

nykademus

I forgot to add that I am working on the assumption that there might be more than one issue that happened to show up at the same time, or was caused by the first.

I figure that the vacuum issue is present and will need to be addressed for certain.

nykademus

Found what the smell was, but I don't know what is leaking yet. It seems like its coming from above the front differential. Does not smell like engine oil.

Any ideas?

guyina4x4

did you stick your finger in it?
not that many choices for what fluid it is, touch it, look at it up close, smell it
should be obvious if it's gear oil or motor oil or power steering fluid

LariatDude

probably busted the diff when driving around in 4x4

HeathMc

Isn't this about where the power steering line issues are? Trace the power steering line down to where it attaches to a frame cross member. Will be a clamp and it sits in a rubber bushing. Pretty common issue. But that doesn't explain the grinding noise. Could be two completely different issues you are chasing.

redfishtd

seems higher than front diff

nykademus

I took a closer look after work and found out that its engine oil. There does not appear to be any place that it SHOULD leak from on the engine, but I noticed that the dipstick tube had fresh/wet oil on it, so I am thinking that with the cold weather, maybe the PCV valve stuck and the pressure built up enough to push it out the top of the tube. That seems to be the only explanation at this point.

The noise IS one of the hubs, I think it has developed an issue with the vacuum system somewhere.

Why does this stuff never happen in June?