Mechanics

4 WHL LO CLUNK

1999 Ford Ranger • 3.0L V6 4WD Manual • 150,000 miles

Hi! Can anyone help to identify the source of this clunk? I use 2nd gear, 4 whl drive lo daily going up and down a track on my property. Recently, but only periodically, I get a big metallic CLUNK going either up or down the grade. And only in 2nd lo. Have never had it happen in 1st low or 1st high, the only other 4 whl dr gears I use. I'm going very slow and it seems to always happen when speed is consistent and there is no jarring motion from dips or bumps. The track it happens on is about 1/4 mile and it might happen only once along the way and I'm able to continue on in the same gear in a normal manner. Because it happens only in 2nd lo and it does feel like the source is directly below me, I'm inclined to think it's coming from the transfer case. Perhaps some sort of a momentary skip or slip? Thanks
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Gthawus
June 28, 2014.




The transfer case won't slip. Have you checked u-joints and CV joints?

Hi jacobandnicholas! A quick check and the driveshaft/u-joints feel ok and the cv joint boots are good. The question that stands out in my mind is why this clunk is in only 2nd gear, 4 whl lo. I've been driving this road/track for over 10 years and this has only started happening in the last couple months. Currently to avoid the clunk 1st gear 4whl Hi is used but this makes me go faster than I'd like to, but there's never been a clunk in it. Occasionally, I'll use 1st gear 4whl Lo when I've got a heavy load and never a clunk in it either. Mysterious, huh? Thanks, gthawus

Tiny
Gthawus
Jun 30, 2014.
If it only happens in 2nd gear low range, that is odd. It never happens in 2nd gear high range?

Been trying to think of a place to try out 2nd gear, 4 whl Hi and haven't come up with the spot. That would be much to fast for my road, probably something you would use on snow or ice. I'll find the right spot and let you know. Thanks
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Tiny
Gthawus
Jul 2, 2014.

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