Rear suspension work
- Thread starter SixBanger
- Start date
SixBanger
Well-Known Member
Odiron, from work to home I did count the amount of speed bumps! So many here. Most are low speed, 30 mph but some 45. This is the way how the country try to control speed on non highway roads. Or to destroy our old suspension! 
HD 5 leaf springs will be great for here. Maybe some local shop could make them. I have contact one seller. $250 for springs plus 350 shipping and then 21% tax. Ofcourse they are heavy and big!
HD 5 leaf springs will be great for here. Maybe some local shop could make them. I have contact one seller. $250 for springs plus 350 shipping and then 21% tax. Ofcourse they are heavy and big!
SixBanger
Well-Known Member
Good idea. I would look around. I did deliver once an clutch for an bus at an truck serviceshop. Thing was heavy, and the vw caddy didn't like it. Good car for delivery jobs. Some random info
I would think there would have several shops in area who makes/repair leaf springs in your area – sense most trucks there use leaf springs.
All FMJ leaf springs use this for front bushing:
MOOG # SB364 (or compatible).
The oval shape is to help absorb sharp movements – which is good for ride when new but not so much performance or after the rubber deteriorates (gives a sloppy feel).
If a person is getting new springs made – I highly recommend going with a round bushing – much like what Chrysler used in the ‘60’s.
FMJ leaf springs are all 2½” wide (63.5 mm)
Length is 58” (1,473.2 mm)
Front segment (center of front bushing to center bolt) is 24” (609.6 mm)
Rear segment is 34” (863.6 mm)
This is a picture taken from my ’77 wagon (5-leaf spring) 18 months ago.
You can see that I need to get these springs re-arched, in a bad way. I added a white line to picture to place emphasis on the sag.
This is a picture of a ’70 B-body leaf spring – which is like what an FMJ spring looks like (but this spring is a tad too short to fit).
Notes:
- The leaf springs have something between the leaves to prevent them from squeaking over bumps. I have seen rubber/felt to thin metal shims used. Rarely does the shims wear out – but can (or can fall out).
- Spring clamps won’t do any good (mainly there to keep foreign items out, over bumps (like rocks, sticks, etc.).
- The traction bar or Caltrac system is mainly designed to improve traction (or the spring wrap condition as pictured on post #13) for high performance vehicles. If you have a high performance vehicle, getting rid of the ISO-clamp would be a big benefit with traction, as well as 5-leaf spring (over a 4-leaf).
I wouldn’t think traction is a concern for you, at this time (but could be wrong).
Leaf spring sag is what I believe you are experiencing – and getting existing springs re-arched or new springs made will resolve your problem (if I understand your concern, correctly).
I can find a lot of videos online about re-arching existing leaf springs - mainly for Jeeps or trucks but same process applies. Some spring shops will want to see your vehicle before to know how much re-arch to install. Other shops may want you to bring in your old springs (you do all of the removal/re-install labor).
Is this what you are looking for?
BudW
All FMJ leaf springs use this for front bushing:
MOOG # SB364 (or compatible).
The oval shape is to help absorb sharp movements – which is good for ride when new but not so much performance or after the rubber deteriorates (gives a sloppy feel).
If a person is getting new springs made – I highly recommend going with a round bushing – much like what Chrysler used in the ‘60’s.
FMJ leaf springs are all 2½” wide (63.5 mm)
Length is 58” (1,473.2 mm)
Front segment (center of front bushing to center bolt) is 24” (609.6 mm)
Rear segment is 34” (863.6 mm)
This is a picture taken from my ’77 wagon (5-leaf spring) 18 months ago.
You can see that I need to get these springs re-arched, in a bad way. I added a white line to picture to place emphasis on the sag.
This is a picture of a ’70 B-body leaf spring – which is like what an FMJ spring looks like (but this spring is a tad too short to fit).
Notes:
- The leaf springs have something between the leaves to prevent them from squeaking over bumps. I have seen rubber/felt to thin metal shims used. Rarely does the shims wear out – but can (or can fall out).
- Spring clamps won’t do any good (mainly there to keep foreign items out, over bumps (like rocks, sticks, etc.).
- The traction bar or Caltrac system is mainly designed to improve traction (or the spring wrap condition as pictured on post #13) for high performance vehicles. If you have a high performance vehicle, getting rid of the ISO-clamp would be a big benefit with traction, as well as 5-leaf spring (over a 4-leaf).
I wouldn’t think traction is a concern for you, at this time (but could be wrong).
Leaf spring sag is what I believe you are experiencing – and getting existing springs re-arched or new springs made will resolve your problem (if I understand your concern, correctly).
I can find a lot of videos online about re-arching existing leaf springs - mainly for Jeeps or trucks but same process applies. Some spring shops will want to see your vehicle before to know how much re-arch to install. Other shops may want you to bring in your old springs (you do all of the removal/re-install labor).
Is this what you are looking for?
BudW
SixBanger
Well-Known Member
Thanks Bud! Great info and notes. For now my concern is to get good set of rims for the car.
But I agree, the springs has had his best day. I can can use the specs. Maybe they could use the old one as an template.
The car is an nearly std and with /6. But some better handling and traction would be better. It is equipped with the 5-leaf spring.
But I agree, the springs has had his best day. I can can use the specs. Maybe they could use the old one as an template.
The car is an nearly std and with /6. But some better handling and traction would be better. It is equipped with the 5-leaf spring.
89.Fifth
Well-Known Member
(EDIT) The Spec on this graphic is wrong. It should ready 24/34
I bought 5 Leafs with an 8.25 inch arch. Much better than stock in my opinion.
Last edited:
89.Fifth, those are some wonderful pictures you have there. I saved them for future reference.
Where did you get those pictures from?
On leaf springs which I either had re-arched or re-arched myself – I’ve added an extra inch (25.4 mm) and have had good success – much like you added 3/4” (19 mm).
BudW
Where did you get those pictures from?
On leaf springs which I either had re-arched or re-arched myself – I’ve added an extra inch (25.4 mm) and have had good success – much like you added 3/4” (19 mm).
BudW
89.Fifth
Well-Known Member
I simply did a search for "dodge diplomat leaf springs" and found a supplier. I had a set made at Espo Springs according the spec I wanted. Please note that the first graphic is wrong and should read 24/34
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SixBanger
Well-Known Member
Great Thanks for detailed specs (second picture).
SixBanger
Well-Known Member
Thanks Poly, but I would look how the old ones look like when I do remove the springs.
