Just replaced all my front end rubber, but...

Post by **mrsnak** » Fri Jul 10, 2009 3:33 am

1961 pickup.

Still getting a "clunk" on big bumps from what appears to be something related to the steering column/rack.
Replaced all the bushings and rubber everywhere I could find, but column and steering rack are still the same. Units are tight.
Any thoughts?
Anything I can baffle better or should I not worry about it. The rest of the front end is so much better now. Taking it in for alignment tomorrow.

Post by **MarkyB** » Fri Jul 10, 2009 8:29 am

Are the master cylinder bolts the right way round? (heads next to the torsion bar)
The other possibility that comes to mind is the steering rack lacking lubrication and/or the rack damper needing adjustment.

Post by **Peetee** » Fri Jul 10, 2009 9:03 am

It might not be the same problem but I had this after replacing all the bushes and the only thing that cured it was swapping to telescopic dampers. I'm not suggesting you must go the same route but I'm wondering if the problem was something to do with combining the leverage and damping loads on the original (possibly less than perfect)dampers as the conversion involved removing (damping) valves on the original units.

Post by **8009STEVE** » Fri Jul 10, 2009 9:15 am

Still getting a "clunk" on big bumps

Front bump stops?

Post by **mike.perry** » Fri Jul 10, 2009 9:16 am

Try tightening the front shock absorber mounting bollts. It could be that the captive nuts have become "uncaptive" and slackened off.
I blame it on all these infernal road humps

Post by **jaekl** » Fri Jul 10, 2009 1:09 pm

Check the pins in the lower trunnions. If there is any axial looseness between the washers and the casting, it slides back and forth and makes some noise. Either the trunnion itself or the washers or both wear or never was snug. Years ago I rebushed my trunnions and made new pins the same length as the old ones and had a 'clunk'. Then I shortened the pin between washers and all was fine.
Of course now you can get new trunnions.

Post by **jonathon** » Fri Jul 10, 2009 1:17 pm

Did you tighten up the bushes when the car was on the floor at laden weight. If you did the Tie bar bushes have you re checked the front end geometry.
As above, check trunnions for wear and that the thick bottom arm is fully on the eyebolt pin and cup.
Were the eyebolts in good condition ie not ovaled

Post by **MarkyB** » Fri Jul 10, 2009 6:20 pm

Don't go mad when you are tightening the front shock absorber bolts.
It is relatively easy to strip the threads then you have major problems

.

Post by **mrsnak** » Sun Jul 12, 2009 3:29 am

Thanks all, I had the same major clunking over large bumps prior to replacing everything, but although much quieter, and a far smoother ride after alignment, still have a pervasive hard clunking that seems to resonate from the steering column,steering rack.

The shop I had replace the rubber did a great job, and I didn't see anything with a visual inspection up on the lift that would indicate anything problematic.
Even they had no immediate ideas, but I also didn't have them fully pursue it.

It's really more of a thud and rattling after hitting a bump.

Post by **mrsnak** » Sun Jul 12, 2009 3:32 am

8009STEVE wrote:
Still getting a "clunk" on big bumps
Front bump stops?

replaced.

linearaudio · Post by **linearaudio** » Sun Jul 12, 2009 6:14 am

Low oil in a shock absorber on mine did that. I guess there was an initial free movement internally before the damper caught up. Could be worth checking?

Post by **bmcecosse** » Sun Jul 12, 2009 10:06 am

Are the rebound stops in place ? I would go with the damper idea though - drain off the horrible old oil (if there is any) and refill with new 20W50. May help the suspension on more than one count!

Post by **Peetee** » Sun Jul 12, 2009 4:38 pm

Check the tie bar. It's possible they have over tightened it. Not only will that reduce the give available in the bushes but it could also mean the end of the bar is in contact (or makes contact under load) with the chassis leg.

Post by **alzax3** » Sun Jul 12, 2009 8:15 pm

And just as a side possibility since you seem to have covered most everything - could it be the exhaust box clunking? It was on our van when we got it, but with the way noise gets transmitted round, I would have sworn it was suspension related.

Post by **simmitc** » Sun Jul 12, 2009 9:18 pm

Check the bolt and yolk that hold the tie bar to the moving arm. I've seen numerous clunks like this caused by an oval hole in the yolk or tie bar and a worn bolt. This area can get overlooked in the rush to replace all the rubber.