96 f150, 2wd, reg cab, 8' bed, 4.9, 5 spd.

I have this concerning noise I have been trying to isolate. I can't find it. It's in the front of the vehicle, probably drivers side. If I set in a paved parking lot and turn the wheel back and forth, nothing. If I go up on a gradual ramp from the street, I will get it. It a dull metallic bump. doesn't do it every time. It drives fine, no issues there. It had a front alignment about 6 months ago.

It has new shock towers, shocks, coil springs, radius arms, radius arm bushings and radius arm brackets. I jacked up each side and checked the wheel bearings, tightened them only slightly, but that made no difference. While I had the tire off the ground, I put a 1" square steel tube under the wheel and pulled it up against the tire, rocking it so to speak, to check the ball joints. They are tight.

So now I'm down to possibly a few possible ideas; (1) .Coil springs moving about (?) they have the keepers in place at the top. Probably not. (2) The Tie rod ends, center link? Could possibly be, not sure I know how to test them though? Help or recommendations on how to test the front links would be a big help. When each tire was up, I tugged on the suspension arms, they seem tight, but maybe I should have had both wheels up to test for movement.

Anyone have any ideas? Appreciate your help in advance.

 

Axle pivot bushings? Sounds like everything else was changed. Get up on each side with small pry bar and try to move the pivot point of each axle. They aren't too difficult to replace, just need some kind of homemade press to push the bushing out. I used all thread and a couple rings/plates. Couple hours and was all done with both sides.

 

Freightrain, thanks for responding.

The tie rod ends have not been changed. At least they sure don't look like it. the drag link, pitman arm joints all look well used but well lubricated.

Do you know of a way to test to see if any or all of the tie rod ends are bad. Information here would be greatly appreciated. I will go out here shortly and check the axle pivot bushings.

By the way, You have responded to other questions I have posted. Appreciate your help, but I have always wondered what kind of truck you have on your signature page. It reminds me of my brothers.

Thanks, Again.

 

For tie rods, I leave the truck on the ground, and have someone turn the wheel lock to lock
Is your coil spring mounts themselves tight?

 

Tie rod checking? If they have any UP/DOWN slop then they need replaced. Take a block of wood, stack a few to get enough height. Put a pry bar against the stack and against the tie rod end and push upward and see if the joint is sloppy. If so, replace them.

Do the same for any other joint. Try to force the joint in/out and see if it moves. The ball should be tight. If any slop, replace it. It shouldn't take much effort to notice.

The picture in my signature is my 1959 B61 Mack. I've had it since 2001. Long term project that I use to haul my race trailer.

Fall 2001:




Current picture:

 

Thanks Freight,

I just crawled out from under it when I saw you message.

I have her on stands, I can with my hand rotate all of the tie rod connecting linkage. I can rotate it approximately 15 degrees in both directions. I don't see any movement from left to right. Is that sufficient to replace or is that just normal? Being able to rotate it that freely I would expect some wear. I will try to see if there is any left to right movement now then to pry up and down on the linkage to see if they are moving.

That is my brothers Mack! His was painted Green when he got it and is nicknamed "Dill" (it a dill pickle color) He doesn't have all the chrome you have and no sleeper. I think it is a shorter wheel base. He is working on starter now. It is Air start. but body wise they look the same. His might be a 55(?).

I would be interested in what you think about the ease of rotation.

 

ok, I just tried to move the tie rod ends up and down using blocks of wood stacked up until i could get a pinch bar between the wood blocks and the tie rod linkage. I tried at each end, At the center to left hand steering arm and the pitman arm to steering arm, nothing. All tight, no movement.

To test the axle pivot bearing, does the wheels need to be off the ground or on the ground? I have not tried that yet. The look pretty scruffy.

 

Working stiff,

Sorry I missed your response. I guess I never though to check the coil spring keepers to assure they are tight, but I will today. Although my wheel bearing are not very old, maybe a year, I'm wondering if it might be them giving me the cracking sound. I hear it at low speeds and when, for example I'm turning into a driveway or out of the driveway onto the main highway. It's intermittent, doesn't happen every time.

Thanks, I'll check today.

 

They should rotate around on the ball socket, though not sloppy loose. Just smooth. If you can't jack them with a bar, then they are likely still good.

The axle pivot bushings? You likely need to jack the wheels off the ground. You might be able to just stick a bar inbetween and see how bad each moves even with wheels on the ground. Mine were beat up even with only 60K miles, but they were dried out and loose after all the years.

I just put air starter on mine a couple winters ago. I like all the old school stuff. The shiny aluminum tank under the bunk is the start tank.

I just put new alum fuel tanks on it a couple years ago. The steel tanks were getting leaky and the cost for new aluminum wasn't horrible. Of course it's something to keep clean(ugh). This has been a long term project. Every few winters I do something more to it. I upgraded the engine about 3 yrs ago. I did the stretch job/bunk about 6 yrs ago. I also added air ride when I stretched it.

They made the B model from '53-65 in various versions and weight limits from B42 up to B81. The larger the number, the heavier the chassis. Gas power was even numbers, diesel was odd numbers.
There is a website for the old Macks. www.Bigmacktrucks.com Lots of information there.

 

 

With tires up in the air, grab them and see if the bearings are loose. Might just take another partial turn on the nut to snug them up?

Does your brothers truck have the old manual air valve on the floor? Might be bad. I put a brand new button on the dash for mine. I have the old steam valve but didn't want to rely on it. I also rebuild the valve on the tank. Should be easy to get parts for it. Mine holds for months without issue. It sat since mid Oct and still had 100# in it last night while I worked on it. I put a dual pressure gauge in the dash so I can keep an eye on the pressure of that tank. If he has a check valve feeding the start tank, that valve might be leaking back. I've heard of guys once shut down, fanning the air pressure off the main tank to make sure those check valves are set so they don't slow leak backwards. My main system drains down in 4-5 hours. Pretty sure it's the air wiper control that is causing that problem. I've replaced the o ring in it years ago and it held much longer.

 

Freight,
I'm still chasing the noises coming from the front of the 96. Referencing the notes above, where do you recommend prying on the axle beam? Are you prying on the axle beam to try and see if its loose at the axle pivot bushing?

Appreciate your help.

 

Just did some work on a 94 2wd with front end "clunk" noise.

Was the coil spring insulator at the base of the spring, completely gone on one side, disintegrating on the other.

The only way I could get the play to show was with shock loose & the arm at full drop.

I did the axle bushings too, the inner sleeves were worn to hell & gone, lots of play around the bolt.

Just a thought.

 

Check for loose rivets on the frame crossmember. I had a couple that were loose and were allowing the crossmember to move around. Took me forever to track it down. I replaced the rivets with grade 8 bolts and welded a couple spots where the frame rails and crossmember meet to prevent it from happening again.

 

Thanks so much for writing. I'm a bit confused but very interested in what you're telling me. Looking at your picture the spring insulator you are making reference to.....Is that what appears to be a thick white plastic looking washer in your picture? If so, I don't think I have those. New springs, but I'm going to look and see if I have them. Hopefully you can let me know if my assumptions here are correct.