Hi all --

I own a 1987 F-150 4x4, 302, Manual Trans. I am new to the "do-it-yourself" club but really want to learn. I even picked up a copy of the Haynes repair manual for my truck.

Anyway, my project for one of these upcoming weekends, is to go through the 4x4 stuff on the truck before I really have to use it. The manual does a very nice job of explaining how to do all of the maintenance things you typically need to do, but I'm not sure which ones to start with, or which ones might be better done by a mechanic...especially since I'm new to this. Does anyone out there have any recommendations on what to do, what to do first, and what to just leave up to the mechanic?

One other question. I was driving around today with the hubs locked and taking it in and out of 4WD just making sure things were working. Everything seems to be working fine, but there is a humming noise that starts in at about 25mph when the hubs are locked in. This occurs whether or not the truck is actually in 4WD. The little trouble-shooting guide in the front of the manual says the lubricant in the transfer case may be low. I hope that is the extent of the problem. Could it be anything else?

Thanks a ton,
DoktorCorb

 

when i first got my truck i just popped it in 4wd and went wheelin, i didnt even check anything. im not sure about the humming noise, sorry. the most work ive had done to the front is get new bearings and thats because the place i took it to to get it aligned after the lift said i needed some, so they put them in.

 

&nbsp&nbsp&nbsp The transfer case fluid in my truck was low and very old at one point this past winter. Dark as oil and it flowed like molasses. I suppose that will happen when nobody changes it for 96,000 miles! Anyway, I changed it out with fresh ATF and topped it off... the humming I kept hearing at interstate speeds vanished! It has to be the easiest maintenance you'll ever perform on your truck. Took me five minutes. A 3/8" ratchet, three quarts of ATF and a drain pan is all you'll need.

 

I'm not sure what the humming could be, however it's entirely possible that the u-joints are getting old. If they have grease zerks then fill them up til you hear the cracking.

Replace the transfer case fluid. Your manual says how to do it. It's not a hard job.

The front diff fluid possibly needs to be replaced. I have a '89 F-150 4x4 with 165k. I have never replaced the fluid. Replacing the fluid in it is a real PITA. As I understand it you have to take the axles apart. I believe you might be able to get a pump and pull the fluid out through the filler hole.

Do you have the automatic lock or manual locking hubs? If you have the automatic hubs, which is unlikely with a manual transmission, you might have them checked out. They go bad with time.

'93 F-150 loaded and modified!
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