1993 B6 5 Speed Front End Noise [Solved]

[CaffeineTripp]

Clunking from front end near wheels, only over bumps, of course.

Replaced sway bar end links, struts, strut mounts. Control arm bushings on both sides are in good condition. Tie rods and ball joints are tight. Rack and pinion mounts are fine. Sway bar bushings at frame are good. Front engine/transmission mount is worn but there is no sufficient rocking of engine during throttle. While lifting vehicle and then applying pressure to rear of crossmember with another jack, there is some movement, about half inch or so, until there is no movement at all, assume that rear transmission mount is probably cause.

May replace rear control arm bushings anyway since I've got a set of 323 ES Poly.

The knocking noise was apparent before the replacement of the sway bar end links and the struts. Fortunately, they needed to be done anyway, but it has not alleviated the problem. I cannot tell where the specific knocking is coming from by applying pressure to anywhere on the vehicle, it only happens when vehicle is in motion, 10+ MPH.

Suggestions?

[Sleeper6]

How are the ball joints?

[CaffeineTripp]

Tight as tight can be. I may, however, remove the spindle from the ball joints and check to see if there's play, but it doesn't seem that there will be just from moving the wheels; everything is solid.

[SuperK]

that bolt that holds the ball joint in the spindle sometimes will wear a groove and cause a clunk. you may want to remove the bolt and inspect it for any odd wear and replace as necessary. That little bolt is pretty important, because of a bit of wear my ball joint jumped off the spindle while driving... oh my..

Also it could be something like the control arm isn't bolted down tight to the rear bushing.

[CaffeineTripp]

Ended up removing the passenger control arm yesterday to check for cracking anywhere. Looked at the bolts that hold the ball joint in and they were fine. Checked bolts and tightness of them for the control arm and they were a bit of a PITA to remove, so they're definitely good. Removed the rear bushing and it was pretty cracked. Sprayed penetrant on one side and watched as it seeped through to the otherside.

Hopefully when I replace these rear bushings it will get rid of the clank.

Did a bit of digging on the part number; Beck-Arnley 101-6191. Most of the websites show that it will only fit 1995-1998 MX-3, which is odd since the U.S. had them discontinued after, what, 1994/1995? But they are essentially the same thing and, yet another sit, lists that they will fit.
Just wanted to make sure that this would be the case given that manufacturers can change thing slightly over the years to fix problems or create a better solution.

Still have some Energy Suspension Rear Control Arm Bushings though that will be used on the '92.

[CaffeineTripp]

Purchased the rear bushings for the control arm on the vehicle, should be arriving sometime next week. Got them from RockAuto for $44.73 shipped. I'll end up doing a comparison of the old and the new for mounting and rubber bushing itself.

Simply haven't had time to get the parts and install parts lately! Way too much work!

[CaffeineTripp]

The bushings came in just today, might get some time to put them on this Sunday or Tuesday.







The part number from Beck/Arnley is 101-6191 and 101-6192. They list as only fitting a 1995 MX-3, but should fit the 1992-1994 as well, at least that's what I'm hoping.

[CaffeineTripp]

Ended up replacing the passenger side bushings since I know it's bad. Here's the comparison from the 1993's and the new '95's.



The difference in the outer bolt hole is only slight. There's more material, but it doesn't come into contact with the rest of the body.



The inner bolt holes are nearly identical with only a bit of an ellipse for the bolt holes.



The OEM U-shape has quite a bit more metal on it and seems to be beefier.





As you can see the rubber in the OEM bushing is has pretty much cracked all the way through and is very easy to push about with minimal force.



The bottom side shows how much more metal is on the bushings itself from OEM compared to aftermarket.

Unfortunately, the bushing replacement has yet to solve the problem of the clunking noise coming from this area. Since the bushings were so worn anyway it was still a good idea to replace them and knocks out one possible cause for it. In any case, the entire front suspension might end up being replaced.

Everything else is still tight in the front; sway bar links, ball joints, tie rod ends, new struts and strut mounts/bushings in 2013. Only thing left would be to replace the front control arm bushings, switch to solid sway bar end links, and replace the sway bar frame bushings with polyurethane.

[CaffeineTripp]

Doing a little more digging I've found that the front engine/transmission mount is bad as well.



As you can see, the transmission is basically sitting on the bottom of the mount itself. The mount is gone, completely. This may cause part of the knocking problem from the front end with the engine and transmission putting their full weight onto the crossmember going over bumps. I expect the rear mount to look the same as well.

I ordered the part from O'Reilly's for $18.00 (PN 8064 Anchor) and will hopefully be able to put it in this coming Sunday including doing the 'poor man's' polyurethane mod by using caulking. Or maybe just go with the King 6 Fab mounts all around like the KL swapped MX we've got. Either or should help immensely.

[CaffeineTripp]

Got a side-by-side comparison of the old front engine mount and the brand new one from Anchor (PN 8064).



The picture doesn't really do the old one justice. The brand new mount does help with the response of the engine a bit, but more of the mounts will have to be replaced. Still had the knocking noise this afternoon.

Figured that I would give one other option a try; tightening the top strut nut on the passenger side first. And that's the clunking noise. The strut nut either backed itself off or didn't get tight enough initially. I will have to spray some penetrant on the driver's side nut to loosen it up enough to allow me to tighten it. Unfortunately, there's no good way besides putting an 18MM socket held by vice grips and using a 1/4" extension with the 7MM socket to hold the strut. I'd rather not pay for a specialty tool (and I've tried the Ford specialty tool but the sockets do not fit), so I'll have to get an 18MM socket with a hex end to help.