Can I just give up on using 4X4 and be okay in 4x2?

WEBDOZER

MEMBER
1997 FORD F-150
5.0L
V8
4WD
AUTOMATIC
270,000 MILES

My 4-wheel drive is having trouble. I can still put it into 4x4 okay, but after a few seconds of driving it starts to make a whirring noise and maybe gets hot.
A mechanic is telling me the problem is with the front diff. It's leaking fluid (nearly out) and he seems to think that the differential is shot (even though 4x4 still works).

My question is, can I just give up on using 4x4 and be okay in 4x2? The mechanic says that I can refill the fluid in the front differential (and then monitor it), but he also thinks that even in 4x2, the differential will seize up eventually and the truck won't run.

Thanks a million.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

The issue sounds like a bearing issue that is most likely in the front differential. I suspect you and the mechanic are correct that it is coming from there and it is caused by heat. However, if this does not do it in 4WD then you are just fine in 2WD. However, the mechanic is correct that if this is a bearing then you do need to fill the front differential so that this bearing gets the proper lubrication. If not, it can seize and you will have issues.

If you care to fix the issue then the only way to know what it is, is to remove the front diff cover and inspect the gears and bearing.

Here is a video that shows how to add fluid on a rear differential. It is on a later model but the process is similar.

https://youtu.be/v1hjDkQb41I

Let me know what questions you have and we can go from there. Thanks

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