Clunk over bumps - Diesel Forum

xr7gt · 04-23-2001, 08:18 PM

It's always sort of been there, a clunk under the floor board area when you hit a big bump a certain way. Never hear it on the highway, only around town. I know, bad Michigan roads, but it should not be there. Has anyone had the sway bar end links replaced or the cab mount bolt under the drivers feet? Everything is tight, but it still occurs. Any new ideas? I like this truck alot even without the diesel(coulda had a V8) but this clunk has got to go.

Billibo · 04-23-2001, 10:19 PM

My wife drives an X like yours and I have heard the same noise many times. Seems to happen when the front right tire goes over a bump or hole but not every time. At first I thought it was a broken motor mount or something heavy bouncing around. Haven't done anything about it yet and it's going on a year

erlong · 04-23-2001, 11:03 PM

There's a TSB out for the clunking that comes from the left rear. I had that one done but the clunking is back. I also now have clunking up front, and it feels like it's coming underneath the driver's seat area, possibly a swaybar link or something. I agree that is is very annoying.

This is one in a list of several things that's getting fixed on my Excursion when it goes in for service this Friday. Will post my results, but it won't be until next week.

POLR BR · 04-24-2001, 01:09 AM

My X did the same thing when new. I don't think it is the cab mounts as it is quite different from the CC which does have a cab mount bushing problem which WILL be fixed this Friday. My clunk went away after I changed shocks, steering stabilizer, and tires. I think it had to do with the X bottoming out frequently because of the inadequate travel distance between the bump stop and the top of the spring pack which is a measely 1/2". I am not sure which item(s) did the trick as they all happened within a few thousand miles. Now that I have the 550 springs, I have plenty of spring travel, almost 3". I note that xr7gt has changed shocks/steering stabilizer. Perhaps he should check his shocks again as there have been some reports of premature failure of the IAS shocks.

erlong · 04-24-2001, 01:45 AM

I'm running RS9000's up front and a pro comp stabilizer shock. Still running the stock leaf springs and tires..definitely clunky. We'll see what the dealer comes up with.

xr7gt · 04-24-2001, 09:53 AM

Thanks for the replies. It does seem occur when the right front tire hits a bump, then travels toward the drivers side. I think some sort of lateral movement of the sway bar causes the drivers side upper link to move. I removed the dogbone(link) on the drivers side and noticed there is excessive play where the bolt comes out of the wheel side of the frame. You can see where some of the frame coating is worn larger than the outline of the nut.

The problem is the larger size of the sway bar with weak end links. Just a poor design. I would consider the Hellwig, but it uses the stock end links. Another solution might be to replace the axle mount bushings with poly-urethane, but I have not found a supplier. I think this may limit some of the excess movement of the bar. Plr Br, do you think the Hellwig helped?

I have to go to dealer for dead running board lights on drivers side(filled up with water after this winter), so I'll let them take a look at the front end.

xr7gt · 04-24-2001, 11:54 PM

FYI,

Energy Suspension has a full listing of polyurethane bushings for the Excursion. The sway bar bushings are part 4-5180 (36mm).

AJ'sDad · 04-25-2001, 10:14 AM

If it's a real hard clunk, I can't help you.

But, if it's a rattle/noisy/sorta clanky but w/o a metal on metal sound, it might be your exhaust system.

I always thought it was just the suspension making a racket over bumps. After I added my flexpipe the truck really quieted down over bumps. Good Luck!

Recycled Racing · 04-25-2001, 11:10 AM

your fron sway bar link attaching bolts are necked down to reduce weight. consiquenltly, portions of the bolt are significantly smaller than the hole they go through. When you experience a hard jounce, the link/bolt moves and you hear the clunk.

Replace the factory bolts with some grade 8 1/2" bolts and locknuts (minor line reaming of the holes may be required) and your problems will go away. [img]images/icons/wink.gif[/img]

xr7gt · 04-25-2001, 03:04 PM

More good replies, I don't think it is the exhaust but I'll look. The point about the fasteners is great. That way I could avoid the Ford dealer. Thank's