Things That Go Bump Under The Floor!
Ok, back to the story. If you remember when we last left our hero, me, he was flat on his back under the coach. I had just finished lubricating the left front king pins and tie rod ends as was about to crawl over to the right side to do the same. But when I am under my coach, or anyone else’s vehicle for that matter, my eyes are constantly roaming and I am pushing and pulling and tugging everything in sight.
But I need to go back a bit for some history here. Last fall leaving Seattle for a trip home to New Hampshire, I developed a heavy thumping under the front end on a pretty good sized bump. A look see underneath did not reveal anything at that time, the shock bushings looked good, I worked the shackles with my pinch bar and they looked tight, the tie rod ends and king pins looked good, so I headed east. I tried applying the brakes a little when it happened to see if I had a brake caliper floating a little but the noise did not change.
It was not too bad on the open road until we got to concrete with the divider strips like in New York, then I thought that the front end was going to fall out. I stopped and got under the rig again, but nothing obvious doing a side of the road check. But this time I found it. It would appear that the previous owner removed the rubber bushings from the sway bar assembly and installed Polygraphite bushings.
Now these bushing are sold as the answer to everything including the heartbreak of psoriasis.
But they are hard material compared to rubber. The bushing were not noticeably worn or loose but when I tugged on the left sway bar link to drag myself from one side of the coach to the other I felt the link change position with a bit of a thump. I tried it again and the same reaction. I tried the other side and again the same reaction.
Ok, so now I have stopped my lubrication job and launched into the project of fixing the thing that was going thump in the night or for that matter of fact anytime.
Removing the links that connect the sway bar to the body is no big deal as long as the coach is level. If one wheel is up and the other down, then the sway bar is loaded, twisted, and the links should not be loosened until the wheels are even. There is a nut at either end of these links to remove them. Now I have the old poly bushings in my hand, now what?
I had just bought a set of shock bushings for my Explorer and that was the next job on my list. They were laying on my work bench right beside the old sway bar bushings. Guess what? They had the same outside diameter, the same inside diameter, and were about 1/4 to 3/8 inch thicker. Bingo, I struck gold.
NAPA as well as many good auto parts stores have carrousels with different products on them. I have found that a lot of little car parts can be found on these even though the part description is not what you are going to use the part for.
Well anyway, back under the front of the rig with bushings and tools in hand. Assemble and tighten the retaining nuts, and now the moment of truth. Pull on the link. No movement. The big moment of truth. I have not drained the oil yet so crank it up and drive down our dirt road, 2 1/2 miles to the main road. Several washboard curves that makes the back end of my big pick up skitter sideways. And guess what, the front end is as quiet as a mouse.
Now I really understand that the Poly bushings will last longer than the rubber, but for the quiet ride that I now have in the front of the rig, I will put up with replacing the bushings every couple of years. Well I guess that we had better get back to more under-chassis adventures when we hear our hero say Ouch!
Brad
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