Mars Posted August 11, 2017 Share Posted August 11, 2017 looking for a cause and cure for suicide shake on my 1930 Desoto Link to comment Share on other sites More sharing options...
trimacar Posted August 11, 2017 Share Posted August 11, 2017 Check tire pressure first. If you inflate tires to recommended pressure most shakes will be eliminated. after that, if it doesn't work, than all front end parameters are suspect... camber, toe in, etc.....if the front end hasn't been rebuilt, then it needs attention...I've seen a lot of restored cars where restorer thought front end condition was "good enough", a big mistake... Link to comment Share on other sites More sharing options...
61polara Posted August 11, 2017 Share Posted August 11, 2017 I would also check the tires and wheels for out of round or flat spots from sitting. Link to comment Share on other sites More sharing options...
SC38dls Posted August 12, 2017 Share Posted August 12, 2017 Ball joints, tie rods and be sure to check lug nuts. I had a friend that had new tires put on and on the way home he said the car started shaking. He kept driving it and stopped by my place on the way. I popped the hub caps and he had 1 lug nut left on and the wheel was a mess. The tire place forgot to tighten them and took responsibility. Check the lug nuts! Link to comment Share on other sites More sharing options...
Rusty_OToole Posted August 12, 2017 Share Posted August 12, 2017 (edited) Check all components for wear and get an alignment. Check wheels for wobble and balance. If all else fails you can install a steering damper. Edited August 12, 2017 by Rusty_OToole (see edit history) Link to comment Share on other sites More sharing options...
Bud Tierney Posted August 12, 2017 Share Posted August 12, 2017 You overlooked advising whether this showed up on a car that'd been recently driven with no problems or one that;d been setting for some time and newly taken out, to experience the shaking, by which I assume you mean shimmying (discernible, excessive or violent shaking of car and steering wheel from front wheel failure to track)......... Didn't by any chance just give it a good lubing??? Accumulated crud can take up a lot of slack; squirting full of nice, slick new grease can push crud out, resulting in discovery of considerable wear in king pins, tie rod ends, ad nauseum All the above are possibilities; jack up one wheel at a time,. jiggle for any slack anywhere...... Link to comment Share on other sites More sharing options...
Xander Wildeisen Posted August 12, 2017 Share Posted August 12, 2017 it could be the road. 2 Link to comment Share on other sites More sharing options...
auburnseeker Posted August 12, 2017 Share Posted August 12, 2017 That bridge is some pretty scary stuff. Just think what else some of those fresh out of college looks good on paper guys design. Link to comment Share on other sites More sharing options...
Mars Posted August 12, 2017 Author Share Posted August 12, 2017 Hi,thanks for all the advice. It does start after going over a bump or rough section,but not always.I drive the car everyday,so it's not a flat spot.It hasn't done it for a year or more but I recently rotated the front tires,left to right.Now it's back.Its not always and I'm thinking the tires just need to work in to their new position . Link to comment Share on other sites More sharing options...
Curti Posted August 12, 2017 Share Posted August 12, 2017 There have been many posts on this subject. Do a search on DEATH WOBBLE in general discussion and technical. Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted August 12, 2017 Share Posted August 12, 2017 48 minutes ago, Mars said: Hi,thanks for all the advice. It does start after going over a bump or rough section,but not always.I drive the car everyday,so it's not a flat spot.It hasn't done it for a year or more but I recently rotated the front tires,left to right.Now it's back.Its not always and I'm thinking the tires just need to work in to their new position . I believe you just answered your own question. One of those tires is bad. As in a loose tread or something else. My money is on the wobble going away if the front tires are replaced. Ben Link to comment Share on other sites More sharing options...
Pilgrim65 Posted August 12, 2017 Share Posted August 12, 2017 I had a terrible shake , turned out to be blown inside wall of tyre , looked good exterior wall and tread , but steel gone ,acted like misbalanced , worth a look. good luck resolving. pilgrim Link to comment Share on other sites More sharing options...
keiser31 Posted August 12, 2017 Share Posted August 12, 2017 Have an alignment guy check the wedges on the axle. My 1931 had two on each spring and one on each side was broken. Why they had two on each side is still a mystery. Now there is only one on each side and it goes down the road perfectly. 1 Link to comment Share on other sites More sharing options...
Rusty_OToole Posted August 12, 2017 Share Posted August 12, 2017 Keiser is talking about the caster adjustment, very important part of an alignment job. If springs are broken or sagged or bushings worn it can have the same effect. Link to comment Share on other sites More sharing options...
Mars Posted August 12, 2017 Author Share Posted August 12, 2017 How does one check and adjust the alignment on a 30desoto? And where would I find the numbers? Link to comment Share on other sites More sharing options...
keiser31 Posted August 12, 2017 Share Posted August 12, 2017 (edited) Most alignment shops will be able to set it up for you. Some still have the old specs. Some just go by experience. Do you have an instruction book for the car? That information should be in there. I would look for it in my 1931 Dodge book just to see if it's in there, but who knows where that is in my mess of an office? Edited August 12, 2017 by keiser31 (see edit history) Link to comment Share on other sites More sharing options...
hchris Posted August 13, 2017 Share Posted August 13, 2017 16 hours ago, keiser31 said: Have an alignment guy check the wedges on the axle. My 1931 had two on each spring and one on each side was broken. Why they had two on each side is still a mystery. Now there is only one on each side and it goes down the road perfectly. Keisers the man Link to comment Share on other sites More sharing options...
mrspeedyt Posted August 13, 2017 Share Posted August 13, 2017 (edited) on my 73 chevy 4x4 it was simply replacing the stock steering dampener. made a HUGE difference.. Edited August 13, 2017 by mrspeedyt (see edit history) Link to comment Share on other sites More sharing options...
Larry Schramm Posted August 13, 2017 Share Posted August 13, 2017 Is it a early or late model car? From what I have seen, early cars had a king pin set up and later used a ball joint. If king pin set up would look at the king ping and bushings. Link to comment Share on other sites More sharing options...
Rusty_OToole Posted August 13, 2017 Share Posted August 13, 2017 Safe to say, a 1930 DeSoto has a beam axle and king pins on leaf springs. 2 Link to comment Share on other sites More sharing options...
Spinneyhill Posted August 13, 2017 Share Posted August 13, 2017 The keys are the wheel side swap and rough road or bumps. There seems to be an imbalance in the front wheel & tyre & brake drum combination on at least one of the wheels. My bet is on wear in the steering components to start with. You go over a bump and a wheel gets a sideways shove and it begins to bounce back and forth due to slop in the steering system. Incorrect alignment contributes. Once it starts to bounce, at certain speeds it will resonate back and forth at increasing amplitude. So, go through the steering: the box, the drag link ends, tie rod ends, king pins, wheel bearing = axle nut tightness. A damper will not fix the wear. It will just damp the symptom. These things drove well when new so modification should not be necessary. Camber and castor will affect the way the car drives. If they are correct, the steering should be pretty much self centring, returning to straight ahead when you let go of the steering wheel while driving (slowly) on flat ground. They can also affect the way the tyres wear. The only way to adjust camber is to bend the axle. Castor is adjusted as Keiser said: wedges between the axle and the springs. If the car has had a hard life the axle may be bent and twisted which makes it harder to fix. Link to comment Share on other sites More sharing options...
Rusty_OToole Posted August 13, 2017 Share Posted August 13, 2017 I understand the first DeSoto (1928) was basically a Plymouth with 6 cylinder engine and fancier trim. If the same goes for 1930 maybe the alignment specs are the same as Plymouth. Which doesn't do much good, as a manual that has one should have the other. Link to comment Share on other sites More sharing options...
Larry Schramm Posted August 13, 2017 Share Posted August 13, 2017 With a king pin system, I would put new bushings and maybe king pins in to start. My guess is that they are worn. Link to comment Share on other sites More sharing options...
Spinneyhill Posted August 13, 2017 Share Posted August 13, 2017 If it is a CF De Soto, it should be the same as a Dodge Brothers DC. The only thing in the manual is toe-in, which is 0 to 1/8" wider at the rear at 9" off a level floor. The earliest wheel alignment data I can find is 1935. Castor is +2° for De S, +2° for Dodge, +2° for Plymouth, and + 2° for Chrysler C1-2-3, +1.25° for the others. Camber is +1/2° for all Chrysler, +1/2° for all Dodge, +3/8 or 1/2° for De Soto and +1/2° for Plymouth. King pin inclination is 9.5° for Ply, 10° for SF and 4° for SG, 9.5° for Dodge and 10° for C6, 5.5° for CZ and 4° for C1-2-3. So it seems a pretty fair bet the 1930 De S would be +2° castor, +1/2° for camber, 0 to 1/8" for toe in, 9.5° for king pin inclination. Link to comment Share on other sites More sharing options...
Bud Tierney Posted August 14, 2017 Share Posted August 14, 2017 Looks like king pin assembly shared with all other CCptn, and tie rod ends and intermediate rods (which catalog says must be installed together) shared with Chry and Plymouth, so those parts should be available if needed...and probably holds true for other front end parts... Link to comment Share on other sites More sharing options...
auburnseeker Posted August 14, 2017 Share Posted August 14, 2017 21 hours ago, Spinneyhill said: If it is a CF De Soto, it should be the same as a Dodge Brothers DC. The only thing in the manual is toe-in, which is 0 to 1/8" wider at the rear at 9" off a level floor. The earliest wheel alignment data I can find is 1935. Castor is +2° for De S, +2° for Dodge, +2° for Plymouth, and + 2° for Chrysler C1-2-3, +1.25° for the others. Camber is +1/2° for all Chrysler, +1/2° for all Dodge, +3/8 or 1/2° for De Soto and +1/2° for Plymouth. King pin inclination is 9.5° for Ply, 10° for SF and 4° for SG, 9.5° for Dodge and 10° for C6, 5.5° for CZ and 4° for C1-2-3. So it seems a pretty fair bet the 1930 De S would be +2° castor, +1/2° for camber, 0 to 1/8" for toe in, 9.5° for king pin inclination. Are the specs the same though, as a 1930 has a solid axle and 1935 is an independent suspension? Link to comment Share on other sites More sharing options...
Spinneyhill Posted August 14, 2017 Share Posted August 14, 2017 (edited) 1 hour ago, auburnseeker said: Are the specs the same though, as a 1930 has a solid axle and 1935 is an independent suspension? Those specs are said to be for All vehicles of that year, unless stated. The Chrysler models are given. De Soto I think made two models that year and the Camber is given for both (3/8 and 1/2). The data is from MoToR's Manual, 1947. Under the Chrysler entry there is discussion of conventional axles 1935-38 in the text (but not which models had them). The next section is about the Airstream models C & DeS 1935-36. Perhaps the SF was conventional, SG was the independent system? Edited August 14, 2017 by Spinneyhill (see edit history) Link to comment Share on other sites More sharing options...
Spinneyhill Posted August 14, 2017 Share Posted August 14, 2017 Here is the entry in Dyke's 1937. There is a list of things you can go through. They also give a discussion of wheel alignment but not specifications. Link to comment Share on other sites More sharing options...
keiser31 Posted August 14, 2017 Share Posted August 14, 2017 I found this which is 1932 DeSoto, but the axles setup should be the same. Link to comment Share on other sites More sharing options...
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