Rough Ride | completely rebuilt suspension

[Lbone]

I second the poly lower control arm bushings. I have heard from several different people including the manufacturers of my polyurethane kit that you need to use rubber lower control arm bushings when the rest is all poly or you will experience a banging noise. Winnipeg roads don't help at all either!

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and sweet car btw

 

[mopar 3 B]

That puts the cross member, engine oil pan and exhaust system how far off the ground? The poly lower control arm bushing should be sitting in the rubber bushing outer casing and should have been greased before assembly, tourqed with weight of vehicle on the suspension. Greasing the torsion bars will increase their life and help removal some day but I don't think that.is where the rough ride is coming from. Is the pinion snuber still on the rear axle? With the body that close to the ground the snuber maybe hitting the body on those small bumps.

 

[themechanic]

I assume you knew you would have a harsh ride with your mods (i.e. urethane bushings). BTW, aren't Bilstein shocks adjustable?

 

[kiltedrunner]

I second the poly lower control arm bushings. I have heard from several different people including the manufacturers of my polyurethane kit that you need to use rubber lower control arm bushings when the rest is all poly or you will experience a banging noise. Winnipeg roads don't help at all either!

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and sweet car btw

LOL - yes our roads are crap here in Manitoba! Harsh winter and summer will do that.

I should point out that I installed Firm Feel "greasable lower control arm pivot pins" and greased them after installation. I am using polyurethane bushings in the lower control arms.

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I'm afraid the Bilstein shocks I bought are not adjustable.

 

[Kern Dog]

my 65 coronet big block has .92 t-bars, 1.125" firm feel sway bar, cheapo monroe gas shocks, and 28" tall 70series t/radials up front. thing handles great. i can't imagine needing a 1" t-bar, just my 2 cents.

After switching to the 1.15 T bars from BAC, I can't imagine using a t-bar any smaller than 1.0.
The Bilstein shocks are great. No reason the question them. I'd say your issue may relate to the Urethane bushings. Years ago it was popular to eliminate every rubber bushing to improve handling. I know of guys that even replaced the bushings in the leaf springs with urethane. While the rear bushing/shackle assembly can benefit from urethane, the front spring eye in urethane will transmit MUCH more harshness as compared to a rubber bushing.
Currently, I only have urethane in the strut rod bushings. The UCA/LCA bushings are rubber. The bumpstops are rubber. I do have urethane bushings in the sway bars though, but that doesn't affect ride quality. I have the 1.15 T bars, 1.25 sway bar front, .75 rear. Bilstein shocks, frame connectors welded in place and torque boxes. The relatively short sidewalls of my tires still give a decent ride, maybe comparable to our 2015 Challenger with STP option group.

 

[mmissile]

Better handling on an old car, generally means a harsher ride. Just the nature of things I've seen. Old cars are mushy, and the new ones are firm.

 

[69roadr]

don't rule out your strut rod. i had noise coming from my front end after new build. come to find out, strut rod nut not torqued down.

 

[R/T]

Moog k791 is all one should ever put in the lower control arms, anything else is going to feel like riding on bare rims. Also tighten the nut when the car has sat on the ground for at least half an hour , otherwise you might shorten the bushing's life.

 

[62 Dart Convertible]

I would suspect the strut rod bushes in the k-frame once you said -

Interestingly, I just found out that while I'm riding my brakes over these bumps, they're not as harsh.

Worked it out yet?

Note - all the suggestions of only torquing the LCA pivot once the car is sitting at it's desired height relates ONLY to when you have rubber LCA bush. If you have poly LCA bush it is unnecessary.

I replaced all my front bushes last week, using moog rubber offsets in UCAs for their extra caster adjustment, and poly bush in LCA as rubber always seems to be the achilles heel. I have not found the ride to be anywhere near as harsh as many have said it would. Just my 2C worth.

 

[jeepers007]

I've had an all poly suspension for 20 years, and have none of the harshness described in this thread. Mine is stock ride height though.

 

[kiltedrunner]

Sorry that I haven't updated this post in a while. I ended up chasing some steering gremlins for a while and finally realized that the power steering fluid all over my k-frame wasn't coming from my power steering pump but from a very fine crack in the steering box.

I just replaced the factory steering box with a new Borgeson box and it's bloody awesome! Tight steering and lots of room for headers!

Back to the suspension... I still need to figure out what's making the noise. I'll be working on that in a few weeks when I have more time. Based on all of the feedback I received in the previous posts, I'll be loosening off all of the suspension and then loading it up before re-tightening. To date, I had tightened everything up while the car was on jack-stands and the wheels were dangling. This could be my problem.

More to come!

Cheers

 

[67 Mopar]

Never been a fan of poly bushings myself...

 

[Kern Dog]

Off topic, but why do people continue to omit QUESTION MARKS in posts? I see this all too often lately here, other forums and in texts from people. Quit being lazy.



Urethane bushings everywhere? Ouch...Those will transmit more harshness than rubber bushings. It was a popular thing to do for awhile and even I jumped on that bandwagon with urethane strut rod, bump stop and upper control arm bushings. I kept rubber LCA bushings and even still I wasn't all that happy. I do love a car that can turn corners, so you'd expect me to just live with it. I currently have MOOG offset UCA bushings, stock replacement LCA bushings but the urethane remains in the strut rod locations. I run the Bilsteins like you, but also have 1.15 torsion bars and a 1.25 front sway bar.

 

[65hemi]

Hey kilt, is the car back on all 4 wheels? (Note the use of a question mark.) Make sure you bring it to the Mopar show at Gauthier's on Labour Day Monday.

 

[kiltedrunner]

Hey kilt, is the car back on all 4 wheels? (Note the use of a question mark.) Make sure you bring it to the Mopar show at Gauthier's on Labour Day Monday.

Hey 65hemi,
Thanks for the invite. I'm afraid I had a wee bit of an incident with the aluminum alternator bracket I made. This past weekend it finally fatigued from the vibration and left me somewhat stranded. So my car will be out of commission until I can fabricate a new one - out of steel!


Alternator dropped down onto the k-frame


Looking down beside the electric water pump.


My tensioning device was dragging on the aluminum crank pulley for a few seconds, so I'll need to turn it on my lathe to clean it up a bit.

I have some ideas how to fix this, hopefully I'll find the time before the snow flies!

Needless to say, I'll be there to check out the cars. Thanks again.

 

[Dennis H]

Hey kilt, is the car back on all 4 wheels? (Note the use of a question mark.) Make sure you bring it to the Mopar show at Gauthier's on Labour Day Monday.

You got the question mark, but Labor is spelled LabOr. ;)

 

[kiltedrunner]

You got the question mark, but Labor is spelled LabOr. ;)

LOL, not here in Canada I'm afraid. We still spell many things differently than our US neighbours... see that?

Neighbour, Colour, labour...