Rough Ride Diagnosis

[55 Fargo]

Hi all, I am trying to figure out the source of my rough ride on gravel roads, going over railway tracks, potholes.

My 47 Chrysler Coupe, has not had new parts installed into the front end, she has a decent set of used coils up front, new shocks front and back.

The tie rod ends are in good shape, the king pins have a bit of play, but are fairly tight.

The car sat for a long time, before it started geting driven on a regular basis, it sat for about 20 years or more.

I do have interior noise, because my interior is out, no head liner,door panels, insulation, just carpet on the floor and OEM seats.

I am more concerned of the rippling vibrations on gravel roads.

Could this be, body mount rubbers, or king pins, or control arms, any ideas?

I do not expect the Coupe to ride like my 2005 Dodge Caravan, but it definately needs something..............Thanx Fred

[PatS....]

Fred, I've noticed on my Chrysler that the body mount rubbers are squished and hard as a rockwood

I'm sure they are all shot on all these cars.

I plan on replacing mine if I ever get to that stage...they sure can't be doing much like that and I can't really see anything else causing the rough ride other than the basic design of the car.

[55 Fargo]

Fred' date='

Regardless if you need new body mount rubber, that won't cause a rough ride. Will just squeak and rattle more. My guess is, the reason for the rough ride is the rough gravel road, pot holes and railroad tracks. You need to get that road you live on paved or move to a street that is paved for a smooth ride. Also, don't hit the pot holes, dodge them and go over the tracks a little slower. Modern cars don't ride all that smooth on gravel roads, railroad tracks and over pot holes either.[/quote']

Norm, thats it, sell the house and move to town or a paved road:D , I think this very thought every time I am driving back home from some place.

Just got back from town, went to a meeting, but the downtown of this small city is hopping tonight, as it's Canada Day, and the fireworks start after dark, people are swarming the streets, was glad to get back out of town, I parked my baby on a street:eek: , for over an hour, was nervous leaving her unattended, even though she is still rough.

I am not worried about noise and rattles, I just think the front end, if I replaced everything would ride smoother, possibly:o .

The last couple of nights, the mosquitos have been so bad, you can't even sit outside,Hmmm;) , maybe city living might be not so bad, they spray in the towns and cities.

The car goes down the highway nice and straight, it steers and corners well, I do not see any abnormal front tirewear after a few thousand miles. .............................Fred

[Normspeed]

It's no use Fred, she's shot. Better sell her to me...cheap:p

But if not that, how is your tire pressure? I get a world of difference when I drop from my highway/towing pressures of around 34-36 lbs to my in-town cruising pressures of 30-32. That's with Michelins.

And if you haven't taken a look at the rubber isolater pad between steering box and frame, that can make things harsher. Assuming your car came with that part. They deteriotate and that makes the bolts get loose. Tightening them without a good isolater gives you metal to metal connection to the frame. Also throws off the steering wheel position.

PatS, you've coined a new forum term.

[BloodyKnuckles]

This may be a shot in the dark but are your front shocks too long by chance. You may not notice it on paved roads but once you hit the uneven and rough roads the shocks could be bottoming out causing the harsh vibrating you had described. Look to make sure you have plenty of up travel with your shocks.

BloodyKnuckles

[55 Fargo]

Hi Normspeed, tire pressure is 32 lbs, steering box is tight to the frame, on pavement she is tickety boo, on gravel a little rough, as I have mentioned the noise is from lack of insulation inside, and the interior is out, so once that is done, it will be a lot quieter, I am sure............Fred

[55 Fargo]

No the shocks are fine, exact match for the OEM shock, it's just an old car ride on gravel, is a little rough, not really a big deal, just figure, maybe I need king pins or something, plan to rebuild the front end in the future............Fred

[Normspeed]

Are you running bias plies or radials? You might try dropping to 28 lbs or maybe even a little less. Just try to avoid the big rocks...

Have you looked at that isolater pad? On my 53 it was bad. Still is, but I did take up a couple turns on the nuts and bolts that secure it. It's a thick rubber pad between the steering box and the frame.

[randroid]

Rockwood,

This may sound overly simple, but when was the last time you lubed it? Lift the frame with jacks to get all pressure off the joints, then pump fresh grease into the zerks, not until you begin to see the old grease come out but until you see the fresh grease oozing. It really makes a difference and it a cheap fix, not to mention a cheap preventive measure.

I may be way off base with this suggestion but until you do it, it won't ever get done. Think of it as chicken soup. It certainly made a difference to my ride.

-Randy

[Allan Faust]

PatS, you've coined a new forum term.

Yep Pat... you did it... first there was UnderCoatney, now there's hard as Rockwood....

Allan

[Normspeed]

This could lead even to the Rockwood scale of hardness.

[55 Fargo]

Rockwood,

This may sound overly simple, but when was the last time you lubed it? Lift the frame with jacks to get all pressure off the joints, then pump fresh grease into the zerks, not until you begin to see the old grease come out but until you see the fresh grease oozing. It really makes a difference and it a cheap fix, not to mention a cheap preventive measure.

I may be way off base with this suggestion but until you do it, it won't ever get done. Think of it as chicken soup. It certainly made a difference to my ride.

-Randy

Randy, this is a good idea, as the last time I greased her up was early spring, the car was not jacked up, some of the zerks did not want to take any rease easily.

I remember an old time mechanic telling me he would heat up the parts to be greased, especially if theyhad sat a long time, apparently this would allow the new grease to be injected into the part that wsn't greased for years and was now stiff with hardened old grease...............thanx Fred

[kevinanderson]

Fred-I don't have anything that rides smooth over tracks, potholes and washboard gravel roads. Sound perception can make a big difference in what you think you feel.

[55 Fargo]

True enough Kevin, cuz on Pavement and on the highway the car drives nice and straight down the road, corners and steers fairly well, I do have a little play in the steering box, and adjusting it anymore is not an option, it needs to be rebuilt.........Thanx Fred

[55 Fargo]

Fred' date='

Someone mentioned tire pressure. 32 lbs is probably too much. My P15 says use 24 lbs but I run with 28 lbs. Like the other person mentioned, try lowering the pressure down to 28 lbs. and see how it rides then.[/quote']

Use this pressure even with radial tires?

[p10plymouth]

Hi Fred ... Just a suggestion put it on the rack(lift) and see if everything is tight most of the time the wheel bearings loosen up and give a sway or uncontrollable steering.. Next is a big thing! check ride height if you used used coils ... why? was it sagging the back springs could be where your problem is checking spring height and comparing it to the alignment specs is the only way... most people get alignments in good weather ... gravel roads snow wet driving conditions only bring out the worst in a bad align car.. hope this helps ..Daniel

[55 Fargo]

Hi Daniel, thanks for the reply good to hear from you.

I have had her up on the air, when the vehicle safety was done in March, the mechanic said all was tight, with the exception of the steering box, a bit of play there.

The car steers and handles well on gravel, it's just dang noisy and lots of vibration, far more than my modern vehicles.

I do have brand new shocks on her, the springs were installed as the old ones were gone when I first got the car, there was really no front end.

The interior is out with the exception of the seats and carpet, so it does get noisy as well, my radial tires have about 32 lbs of air in them, so should I deflate them to 28 to soften the ride, so to speak.

The car sits nice, no sagging, so not sure if the rear springs are any good or not, they are old and probably need to be replaced someday..............Fred

[david lazarus]

Before I completed the interior on the '38 it was very loud, but I expected that noise would bounce inside an unlined car. What did suprise me was how quieter it became when I did complete the interior and then the car became smoother still when I put new radials on. The old Xply tyres were 30 years old and hard as hell.

[55 Fargo]

Although my tires are modern radials Good Year Wrangler RT/S, P205 75 15s they have miles on tem, and are about 7 to 10 yo, bought them used from a friend, he laos had them on his 48 Chrysler for a few years, lots of tread, but could be hard tire, they are getting old.

[kevinanderson]

Don't Wranglers have a stiffer sidewall?

[55 Fargo]

I have no idea, being a litght truck or SUV tire, it just may have a stiffer side wall.

When I can afford new tires, I am thinking of Wallyworld Radials........Fred

[kevinanderson]

Fred-That's where I bought mine. Kevin

[55 Fargo]

Hey Shel, "wadda ya mean slow down", ah what fun is that, right now the road is groomed fairly well, always cruise at 40 to 50 mph down it.

Now wonder it feels ruff, but I love driving this car, gonna go into withdrawl once I seriously start the bodywork, cuz she won't be driven at that time, till the bodywork and paint gets completed...........Fred

[55 Fargo]

You are right Norm, my fussy pride does not want me to drive any car with bondo filler freshly applied to it, but heck as you say, I would work 1 panel, then prime.

I figure I may as well try some bodywork soon, it will be getting muggy hot here now, but nothing like my Southern Brothers have been getting for a while now..........Fred

[Young Ed]

Fred have you seen my car?? Keep driving it!