WTB: Rear lowering coil springs

[chevy_fatman]

Hello, looking to buy some cheap rear lowering coil springs (4 in. or more) for my '71 C-10, used ones would work as they're intended for my beater, if anybody has a pair laying around that wants to get rid of please let me know.

Thank you. fatman.

[stllookn]

I hear the GM "A" body springs work fine but I am unsure of how much they drop the rear of the truck. I picked up a set at a swap meet for $10 and am dying to give them a try. I should finish my exhaust this week and then they are going on! I'll let you know...if you can wait.

[chevy_fatman]

Sure! let me know how they fit and low they get your truck, if you don't mind.

I appreciate the reply. fatman.

[Frank_Zeller]

I bought a MOOG coil spring catalog to investage this. Based on info in the book the A body springs are a direct replacement. Looks like they would give 3 to 4 inches of drop. Look on ebay they go for 10-25 dollars. Search "Rear Coil Springs"

link to one pair but they are new

http://cgi.ebay.com/ebaymotors/ws/eB...category=42606

[chevy_fatman]

Thanks for the info Frank!, do you also know between what years will fit? Thank you for the link man.

fatman.

[Old Chevy Lover]

stllookn - came across this post, and wondered if you ever installed these. Was wondering how much of a drop it gave you..

[72addict]

I put a set on the rear of my 1/2 ton. moog p#5409

[68 Suburban]

Originally posted by 72addict
I put a set on the rear of my 1/2 ton. moog p#5409

So how much of a drop do you figure? Andf how is the ride? Have you driven with any weight in the back? Thanks

[72addict]

Haven't loaded anything in back. Don't have the truck plated yet either. I'll let you know.

[70c10]

what size are those rims?

[Old Chevy Lover]

did you measure before and after you installed the springs to see how much drop there was?
also, here is a link that has a chart at the bottom that shows the part numbers to different springs of differnt cars if anyone is interested..
http://site18951.dellhost.com/gfiles/g_spring.html

[Old Chevy Lover]

Here is another link that has some spring info, and how to figure ride height, load height, etc...
http://www.hotrodbuick.com/springs.html

[Blue68]

Frank_Zeller,
What does the Moog catalog say that the spring rate, load height, and free height for the replacement springs on our trucks? I believe the part numbers are like 6101 and CC603.

Also, any ideas on the rear weights? I'm guessing about 1600lb minus whatever a rear axle weighs, or around a sprung weight of 1300lbs?

And...If you are going to try and grab a specific set of springs from an A-body or G-body in the salvage yard, how do you know what to look for?

[Frank_Zeller]

I will look the info up tonight.

[Frank_Zeller]

The is from the 1996 version of the MOOG Coil spring catalog

Stock 1967-72 rear C10 #6101 or CC603 (comfort coil)

6101 stats 5.5 ID Wire Dia 0.740 load height 8.75 load 1700 rate at load height 382 Free height 13.197 pig tail type 3


5409 is listed as a B skylark 72-71, C Malibu 68-67 Cutlass 1968 P tempest 1967

Stats 5.530 ID wire dia 0.552 ID load height 7.50 load 849 rate load 140 free height 13.53 pig tail type 19

to lower the rear I would get the #5401

Cutlass 69-68
GTO 1969
Lemans 1969


or Shortest spring

5385 5.53 ID 0.58 wire dia 9.0 load height load rate 166 free height 12.6 pig tail type 19

B Skylark 72-67
C Chevelle 72-71
C Malibu 72-71,69-68
P Grand Prix 72-69

Or go out to the junk yard and get some used ones from any of the above listed vehicles or ebay.



Frank

[Old Chevy Lover]

Thanks for the spec's, Frank! On the 5385, I think you left out the load rate at loaded height.

[Frank_Zeller]

#5385
5.53 ID
0.58 wire dia
602 load
9.0 load height
load rate 166
free height 12.6
pig tail type 19

#5401
5.53 ID
0.531 wire dia
726 load
7.5 load height
load rate 128
free height 13.159
pig tail type 19


#5409
5.530 ID
0.552 wire dia
849 load
7.50 load height
rate load 140
free height 13.53
pig tail type 19

Stock Spring
#6101
5.5 ID
0.760 wire dia
1700 load
8.75 load height
rate load 382
free height 13.197
pig tail type 3

Think I got it right this time.

[Old Chevy Lover]

Thanks man.. I was looking for that 602 number..

[Blue68]

Ok, now I'm confused. The 6101 load ratings look a lot like front spring ratings. At 1700 per spring, you would have to load 2500 (based on the springs being inside the lever aka trailing arms) pounds at the rear to get it to load height.

And this is twice as much force as any of the other springs listed, yet 72addict's truck isn't sitting on the bump stops. To get to the same loaded force of 1700 pounds, the 5409 spring would be coil bound. The 6102 is I think the front spring for the same truck, and these numbers would make more sense on the front except I'm pretty sure the front springs are much taller than 13 inches, right?

Am I missing something here? I'll admit to not knowing how to calculate for levers, but it would seem that at some point (ideally 3 inches or so lower than stock) the other springs must exhibit similar load force to hold the truck up.

[Old Chevy Lover]

Hey Frank,
Could I possibly trouble you to find the spec's for CC501 Moog springs in your catalog? I have looked on the web, and can't find them published anywhere.

[Frank_Zeller]

CC stands for Variable Rate. The rear CC coils I've seen have a tapered coil winding.

My Catalog does not list the spring details other than application.

CC501 is rear coil for

B Skylark 72-67
C Chevelle 72-71
O Cutlass 72-67
P GTO 71-69
P Grand Prix 72-69

[Old Chevy Lover]

From the applications you listed (these and the earlier ones), it looks like its similiar to the 5385 applications. Being that this is a variable rate spring, looks like it would be better suited for a truck. Thanks for the info, again!!!

[Old Chevy Lover]

Installed the Moog CC501 springs on the back of my truck. Gave me a 3 1/4 inch drop when let back down on concrete. Don't know if new coil springs 'settle' any once driven or not.

[Frank_Zeller]

Great..........

[Old Chevy Lover]

Thanks again Frank for all your willingness to help and information!