Rear and front suspension,

[nascarjeff63]

Hello, 

    I'm new to the group, I just acquired my father's 1947 Plymouth club coupe. He only had if for a couple of years before he passed in 2021, so he didn't get to fix or change things he wanted to do. He was a lifelong Mopar man. I found the car locally for him as something he could actually fix up and already in drivable condition. The car is not stock as the previous owner made it a hot rod and put a SB chevy engine in it. I am in no position to change the powertrain at the present time, but I need to make it safe and drivable.

  Driving it I noticed the suspension in wobbly. Looking underneath the rear leaf springs bushings are shot. So, should I just replace the bushings or just get new leaf springs? Shocks look fairly new, but I will replace them anyway. Shock recommendations? Sway bar bushings need replaced. Front squeaks like crazy, how do I tell if control arms need to be re-built? I will eventually switch to front disc brakes, the car has stock front drums a newer style power master cylinder and it looks like a Ford 9' rear end. It is missing the front fender liners so I will be looking for those. I don't know if they would still fit with the V8 but i think they could be modified to fit. 

                                                   Thanks for any advice, Jeff  

[Desert Rat]

@nascarjeff63 My 37' P4 was REALLY clunky. I noticed the noise was worse hitting a dip like a pothole than a bump. So I got some new shocks from MOparts. Changed out the front shocks, adjusted brakes and did a chassis lube up front and it was a night and day difference. Still have the rears to do but I ran out of time over the weekend. 

Not sure if this helps you but maybe someone else. .Cheers 

[Loren]

I have to toss my 2 cents in here.

When I was in college I had a 49 Special Deluxe that got ZERO maintenance.

I rode nicely and never gave any trouble.

My friend had a 68 Ford Torino GT (which was 2 years old at the time).

His car squeaked from the front suspension every time it moved. EEY EEY EEY. It sounded like two teenagers on an old spring mattress!

It was so embarrassing, he did a lot of walking.

Now the Plymouth had metal to metal bushings in its suspension, but the Ford had full rubber isolated suspension.

Yet the old Plymouth was silent and so was every one I have ever seen.

SO...before you "modernize" your Plymouth you might want to consider this.

Just sayn'

[Sniper]

The issue with the 49's suspension isn't the bushings, it's the geometry.  Unless your sole criteria of a good suspension is based on "does it squeak" then it doesn't matter.

 

Bumpsteer is bad.

 

Front shock upper location is poorly chosen.

 

Anti-dive is minimal.

 

Rear suspension wheel hops badly in a curve driven enthusiastically.

 

It might have passed muster in 49, but not so much today.

 

 

 

 

[James_Douglas]

Hello,

 

I would replace the silent block (front of the rear leaf spring) and the rear shackle bushings. Then I would make sure you grease the from end VERY well. Check the grease in the front wheel bearings and set them to the book specification for end play, not the tighten the nut then back off one flat shade tree approach. You may have to get a shim or sand the thrust washer behind the nut to get it perfect. This last step can make a much larger difference in these old cars than most people think.

 

Then take it for a ride. If it still feels bad when driving it, then you may have to pull the king pins and the spindle and have new bushings put in. I STRONGLY recommend that you try and find a king pin set that has the bushing-bearing not the bushing-bushing. See my old posts on my 1949 Convertible. The bushing-bearing combination makes for MUCH lighter steering.

 

Then take it into a shop and have an alignment done. Have them do a "Tram" measurement to make sure that the 9 inch ford was put in parallel to the front end. Check the castor and have them give as much as you can get within the specifications. Also, make sure you are using the narrowest tires you can get if using modern radials as the contact patch was much smaller on the old tires and the steering is stiffer with wider ones.  DB Tire makes a radial with a small contact patch that looks like the old tires, but they are not cheap.

 

Go through the steering box adjustments in the service manual to make sure it is correct.

 

After all that you should be ok. If not, then some more serious is going on.

 

James

[Plymouthy Adams]

I have replaced the silent block...but to be honest I have never replaced a failed silent block...these are very hardy built.  The shackle bushing are however very much a wear item and you will want to change these for sure.  ODDS are your shackle bolts may be damaged due to banging metal to metal because of shot rubber inserts.  Inspect these for certain.  If you springs are not curve and lost their arch, there is no need to replace these....UNLESS the shackle bolts have beaten these silly and out of round.  You then would replace or consider sleeving the eye.