1965 c20 suspension questions.

[Green chevy c20]

Hi how its going. I have a 1965 chevy c20 truck. This truck has the stock suspension with the coils up front and coil with the left springs in the back. When you drive this truck on a straight road it drives very nice,but as soon as you hit some bumps the truck is very bouncy.I think it is due to the stiff springs in the rear. I have kyb gas ajust in the shocks in the front in rear. I just want to try to get a little better ride as i am going down the street as it is my daily driver. I think i have about 500 dollars max to spend. Just wanted to see what you guys think. i heard from a friend of mine that you could maybe put c10 springs in the rear. or i was looking at some dual rates springs but not sure about them. The only thing i will ever tow is a small boat so i dont need a stiff rear suspension. I was also thinking to leave the front alone and get softer springs for the rear and hopefully it will drive better. Thanks for any advice.

[Mathew21]

Welcome,

I installed stock C10 springs in the back of my 66' C20 before I lowered it. Post up some pictures of your truck when you get a chance.

[Green chevy c20]

Thanks for the reply. Did the c10 spring ride better then the c20 springs?

[Mossbeard]

I have a '66 C20 with the same issue. Trips over bumpy roads are brutal. I'll be curious to see if a spring swap from a C10 changes the ride. I'm also curious if the ride height is the same?

I discovered that my truck rides beautifully if I put about 400lbs of building material in the back. Barely even noticed potholes. Ride's great. My daughter suggests that I just buy 400lbs of cement and enjoy the ride!

That's a NICE looking C-20. Take good care of her.

Good Luck, and keep us informed if you find a solution!

~ M

[Mathew21]

Originally Posted by Green chevy c20

Thanks for the reply. Did the c10 spring ride better then the c20 springs?

Wow that's a beautiful truck!

Yes the C10 springs did improve my ride quality. My truck was right about the same ride height after I changed my springs from the "OLD" C20 coils to "BRAND NEW" C10 springs. But I have no idea how old the C20 springs I took out were. What I'm trying to say my old C20 springs might have originally sat higher.

[earl84]

C20's had a regular spring and a heavy duty spring, mine had the heavy duty and it was not fun to drive. I went with airbags with Schrader valves in the rear, and it is considerably better. Still a little rough, but I still have 50 year old shocks on it. That will change next week hopefully.

[factorystock]

Originally Posted by earl84

C20's had a regular spring and a heavy duty spring,

Correct, the standard C 20 coil springs were 2000Lbs, the optional heavy duty C 20 coils springs were 3000lbs. The standard coils ride much nicer than the heavy duty coils when empty. I would just replace your heavy duty c20 coils with standard C 20 coils.

[bullwinkle3331]

Hey Guys,
What is the difference between the two different types of C20 Coil Springs?
Thickness of the spring material, etc.?
If thickness what is the dimension for the Standard and Heavy Duty?

Thanks for the information.

[factorystock]

'66 C 20's will list the heavy duty spring option on their glove box SPIDs. Unfortunately, '65's did not come with glove box SPIDs. Heavy duty 3000lb coils look different than the standard 2000lb coils. The heavy duty 3000lb coils are spread more evenly apart, the standard 2000lb coils are close together, especially towards the center of the coils. C 10's came with 1250lb coils standard, the heavy duty option was the 2000lb coil.

[vince1]

Use the standard shocks, iv'e been told. Not the heavy duty ones.

[earl84]

Yes, the heavy duty springs had thicker coils, but I can't remember the dimensions, and can't locate the info, lost some files on my computer. Go with what factorystock says about the spacing to determine what you have.

[yelmer]

if you buy new springs they will look different the originals The originals are a variable rate spring . they have a tight coiling in the middle of the spring . the new ones they make for replacement do not have this .

[Green chevy c20]

Thanks for all of the advice. I find a way to get it to drive a little better. I was able to get my truck on a lift and found out that the main bearing of the drive shaft was bad as the rubber was almost gone. So I got a new bearing and that help smooth out my ride. Also I put i spare tire behind the rear axle and that helped a lot. So I still have my stock springs on there and with the new bearing on the drive shaft and the spare tire under the bed helped a lot. It's a lot less bouncy. Thanks for all the advice.

[63burban]

LOL, it's a TRUCK, it wants to be used not just driven, load her up !