leaf spring 72 GMC

[Warren]

Starting to research leaf springs 72 GMC C1500. Apologies this will be long.

I had a broken leaf on the passenger side and when I lifted the truck recently found a second broken, the two middle ones, the second had broken over the sharp edge. I did have some fair weight in it so ill admit to operator abuse.

First thought is spring places say just put some new leaves in. Im not leaf experienced, did have a transverse re arched once. My thought is at this age and this being the original leaf the whole thing should be replaced and start fresh.

Few friends said stay stock dont go heavier you will mess up the ride. I do have need to carry stuff from time to time with weight but have other ways then some of it is likely too much for the truck anyway.

Ill leave towing out of this. I have towed a fair bit with a 92 roadmaster, both single and dual wheel trailers. I have a class five hitch on that car and use load equalizers then did tires shocks and cargo coils. Wish the Michelin LTX I put on that car came in beefier sizes for pickup as they have a higher load rating than the TA and an extra side wall, really improved how the car rides and handles. Nother story. Just blurting that out those changes made a big difference.

The stock leaf is G70. There are four leaves with a band only on the front. Spring looks like 52" long. 2 1/4" wide and middle leaves .3150 approx thick, top main one one .3150 as well, bottom looks like 1/2" with long tapers to square ends. Two middle leaves are both tapered to the ends and also rounded on the ends. An old hot rod guy said this is better but you may not find that now rather just straight cut at the ends.

In the printed material it says "G70 includes 1250-lb each capacity two-stage leaf-type rear springs and HD shock absorbers". The plate on the cab says Gross weight 5,400 lbs. Truck Gross weight says 4,600 lbs, Printed material says curb weight 3,742 lbs with a V8. Times ive been on a weigh scale they say around 4,000 lbs. Im not sure how you calculate how much box weight you can have based on those drifting numbers.

As far as ride height the truck sits fairly nice now. Im leaving out drop thoughts for now just get it back to stock. If I was coming down id like to be able to do it is small increments. I realize that with new leaves it will likely sit higher and i wont be keen on that. Maybe they settle a bit. I think someone said there are lowering springs as well but im not going to look into that if doing stock then later date changing shackles to come down in small increments then that feels right. There is some tilt now, that feels right to me so would want to maintain some.

I measured ground to wheel well and get numbers below. Front and rear tires are both TA's, two different width but diameters all the same 28". Truck is lower on the passenger side now both front and rear. Rear pass side the side with the two broken leaves.

31 3/4 Driver front
31 Passenger front

32 Driver Rear
30 7/8 Passenger rear, this side with broken leaves,

so after all that,

Think replacing the whole thing and not just two middle leaves is logical?
Think stock weight like G70 is the right choice to not change ride quality much
Think if ever need be an extra leaf can be added down the road, just want to understand the capabilities. Think so
Bolts bushings replaced, new U bolts
shackle can be sandblasted and painted?
Normally if I have stuff off I sand blast and primer and paint, likely they come raw?
Then am I going to wrestle bolts and some will be stuck, or take it in

You have lots of spring places in the states, Shipping would not be ideal so would check if spring places here sell from any of those manufacturers. Eaton Spring I think the closest being near the border.

you can see its sitting a bit higher on the driver side

Sorry for the long post likely more thoughts as well

thanks

[demian5]

If you can afford it, get a pair of new leaf spring packs and fix that oil leak before you need a new diff as well.

[KY_GMC]

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[Warren]

no oil leak

I rust proof all my vehicles with Fluid Film. Doesnt look great but im driving cars from the 90's that would be trash otherwise. Usually put a gallon and quarter approx or more before on the 92 before winter. Have one that was never done and that one got more first time as some almost soaks in. The truck gets some smaller amount but still gets covered did it last year before it was put away.

Are the long bed springs the same length?

[54blackhornet]

Detroit Spring

[Warren]

ive read a bit on the site and had also emailed them last week On my own I didnt find my spring on the site but saw what they suggest for a chev and two sizes of lowering and higher to either side. They emailed me and will get back to them later in the afternoon

thanks

w

Anyone know what the capacity is of the truck based on my info up above. What are you legally allowed to put in the box provided the leafs are good. Ive had over 900 lbs in there.