Leaf or coil standard rear spring on GMC?
 

I have learned from this board Chevy C10 and C20 came with coils in the rear as standard and leafs was an option and that it was the other way around with the GMC´s, leafs standard and coils as option.

I then saw this GMC sales broshure which claims coils as standard and leafs as option, just like the Chevys.
http://www.lov2xlr8.no/brochures/gmc...p/bilder/7.jpg
It is a Canadian sales broshure so maybe this a a Canadian only thing?

Re: Leaf or coil standard rear spring on GMC?
 

Every GMC I've ever had still had rear leaf suspension as an option on the spid. I don't know why but it just seems like more GMC's had leaf.

Re: Leaf or coil standard rear spring on GMC?
 

the way I heard it was that coils were standard on chevy c 10 and 20 and that leaf springs were optional, and exactly the opposite for GMC's

Re: Leaf or coil standard rear spring on GMC?
 

Here it seems like half and half. Lots of gmc's have coils. Same with chevy's I have noticed lots of the 4 speed trans trucks have leafs

Re: Leaf or coil standard rear spring on GMC?
 

Have not researched this matter, but have owned quite a number of these Chevs/GMs and looked at many more. With pickup type, have come to the following impressions:
1 ton - C30/3500 - leaf rear.
3/4 ton - C20/2500 - leaf rear
1/2 ton - C10/1500 - usually coil rear but some with leaf rear (maybe called "heavy half")
I think every "K" model seen has been leaf front and rear.

Hope this helps - ready to be wrong.

Re: Leaf or coil standard rear spring on GMC?
 

Thanks for replys.
There is in fact both Chevys and GMS´s C10 and C20 of both brands with coils and with leafs.
C30 and up and all K models came with leafs, both Chevy and GMC´s.

The question I had was what type was standard and what type was optional?

For the Chevys I am almost sure coils were standard and leafs was avaliable as an option. At least that is what most people on this forum says and that is also backed up with the information in the sales brochures.

For the GMC´s most people says it was the other way around, leafs standard and coils was an optional. For the GMC´s I haven´t seen any other sales brochure or other documentation than the Canadian broshure posted in this thread.

It would be interesting if anyone have a US GMC sales broshure that states one or the other.

Re: Leaf or coil standard rear spring on GMC?
 

Well...... Yes, all 30/3500's, Longhorns, and 4X4's had leafs. '67-'68 U.S. GMC 4X2 pickups were almost always leaf spring/Dana rear axle, Chevy's were usually coils with Corp. or Eaton axles. '69 and later it seems that anything was optional in everything. I have seen Dana axles with coil springs on Chevy's, ect.. Canadian GMC's are different, pre-'69 they are a lot closer to Chevy's than U.S. GMC's.

I consider my '67 a 'real' GMC. It has a V-6, New Process transmission, and a Dana 60 with leafs. That combination was not available in a Chevy in '67.

Re: Leaf or coil standard rear spring on GMC?
 

It's always been confusing. From what we see out there we could say Chevy = Coils standard/leaf optional and GMC = leaf standard/coil optional. BUT... if you go by the SPIDs, it's all the same. You will never see a SPID showing a "Coil Spring" option. It would seem GM made most all C10-20 GMCs with at least one option, leaf springs. Maybe it was a way to have a difference in base price for gov't order purposes. It seems they always got Chevys

I look at it like automatic transmissions. When I ordered my '92 K3500 I got every option I ever wanted. I wanted a 5spd manual transmission. While almost all trucks came through with automatic, it was still a $1,000 option. I saved that much by going with the standard transmission which is a rare exception in a loaded truck.

Re: Leaf or coil standard rear spring on GMC?
 

I've heard from a very good source that Custom Deluxe had rear leaf springs. If someone has one that came with coils instead, I'd be interested to hear about it.

Re: Leaf or coil standard rear spring on GMC?
 

Can't say for certain, but on our Canadian GMC 910 I remember the coils NOT being on the SPID. It had overloaders that were. But the coils seemed to be part of the base equipment on the GMC based on that.

Re: Leaf or coil standard rear spring on GMC?
 

I have several Salesmen Order-guides from 67 on. It clearly states Coils standard , leaf optional on Chevrolet C-10

Re: Leaf or coil standard rear spring on GMC?
 

I would have to agree with the guy above. My truck is about as bone basic as you can get and it came with rear coils.

Re: Leaf or coil standard rear spring on GMC?
 

I've got a '71 C10 Custom Deluxe with coils plus overload leafs in the rear.

Re: Leaf or coil standard rear spring on GMC?
 

Well, I'd have to scratch that source for being a good one, because that is totally wrong. Trim level had nothing to do with it and anyone who knows anything about these trucks knows that much.
Yes, that's a known fact. The question is were GMCs the same way. I say yes, but they still came through mostly with leafs

Re: Leaf or coil standard rear spring on GMC?
 

In my area (northern Alberta, Canada) 67-72 1/2 tons with rear leafs are rare. I have actually only seen two. One was a 71 Chevy 6 cyl , 4 speed standard, (plain Jane) and the other is my Sons 1970 GMC 1/2 ton 307 3 speed standard.
Pretty sure leafs were an option and seems it was not picked often, at least on the trucks of this era I am familiar with.

Re: Leaf or coil standard rear spring on GMC?
 

I have a 1970 GMC Sierra Grande 1/2 ton 2wd with coils

Re: Leaf or coil standard rear spring on GMC?
 

That´s what I think too.

Re: Leaf or coil standard rear spring on GMC?
 

Ha, well I won't mention who it is, but he's well respected. Can't know em all I guess.

Re: Leaf or coil standard rear spring on GMC?
 

Our 1970 GMC Sierra Grande 1/2 ton 2wd has leafs. It must have been an option.

Re: Leaf or coil standard rear spring on GMC?
 

Just wanted to chime in and say my 69 C-20 4-speed has coils.

I was just assuming the coils were lighter duty than leaf springs.

So much yet to learn for me.

Re: Leaf or coil standard rear spring on GMC?
 

All 67-72 C10 and most C20 pickups had rear coils as base equipment. The same can be said for GMC C1500 and C2500s. There are many ads for GMC clearly stating optional rear leaf springs were available.

The only trucks that came standard with rear leafs were the C20/C2500 Longhorns (133"wb 1 ton frame), C30/C3500s and all K series 4x4 trucks.

Like Special-K Tim said above, "Custom Deluxe" was only a trim level and would in no way affect chassis equipment or options.

Re: Leaf or coil standard rear spring on GMC?
 

My '72 GMC C15 LWB Fender Side has leaf springs and looking for new ones to buy any suggestions ?

Re: Leaf or coil standard rear spring on GMC?
 

My understanding and the information I recall is that GMC always considered themselves a 'leaf sprung' truck...vs. the Chevy system in the 60's which was coil/trailing arms, starting in the early 60's.
As such, the GMC factory default (no option) was that you would get leafs....but you could get coils if you ordered them.
As stated above, Chevy was the opposite....coils were standard but you could get leafs, ...if you ordered them.
The GMC marketing literature from the mid 60's always emphasized this 'leaf spring' advantage...as well as their 'dual' headlight advantage (lol).
Regardless, and as a result you see both types of trucks out there with both types of suspension depending on what the owner wanted, ordered or expected.

However, if you pay close attention you will probably see that GMC's are more likely to have leafs....at least that has certainly been my experience.

All good
Coley

Re: Leaf or coil standard rear spring on GMC?
 

In canada(just talking about canada)
the GMC 910, 920, as we called them, are more-or-less just Chevy trucks with GMC trim

All the canadian GMCs right from around 1960 thru to 68 were called by the 910, 920, 930 etc designation.
Coil springs were for sure the standard equipment with Leafs being optional. I have seen way more 67-68 910s with leafs than chevys, but the leafs are very rare to see on a 910, 920 in canada. and were always an option

Canadian GMCs never had that "custom" emblem on the front fender like the US 67s had.
Canadian GMCs never ever had the V6
Canadian GMCs never had the Color matched instrument panel.
Canadian GMCs use a unique "custom" emblem for the cst door emblem in 67,68
I think there are a ton of other GMC diferences, but as a canadian, i rarely get the oportunity to see a US 67 68 GMC

Basicly any 1967 and 68 US GMC unique features are not on a canadian GMC, like i said, the Canadian GMC is basicly the same as the C10, C20 but with some different trim.

Re: Leaf or coil standard rear spring on GMC?
 

Does it show coils on the SPID?
OP question is whether coil or leaf was standard on GMC - so your SPID could help answer the question for 1/2 tons at least. For Chev, coils were standard on C10 and C20 (except longhorn as Tim mentions) so if one rolled off the line with leafs, it would be annotated on the SPID. So, if leafs were std on GMC, for instance, coils will be on the SPID as they would have had to have been ordered as optional equipment. If your SPID doesn’t list coils, then we can assume coils were std.

72longstepper - your SPID could also provide useful evidence (by showing no options for suspension coil vs leaf)

I have no idea why gmc would have a different suspension as standard equip compared to Chev, but this is not the first time I’ve heard the gmc/leaf story. So am interested to see your SPID kmfb.

Re: Leaf or coil standard rear spring on GMC?
 

My 1970 GMC sales brochure shows leafs as optional not standard. This is a Canadian brochure though if that matters.
My truck option list has G70 for “rear suspension leaf”.
It’s a stepside shortbox.

Re: Leaf or coil standard rear spring on GMC?
 

Salesman guide shows leaf standard, coils optional. My 71 GMC 1500 has leafs and nothing showing on SPID.

Re: Leaf or coil standard rear spring on GMC?
 

That is THE data point. Thanks for checking.
If someone has a GMC with coils that also shows them listed on the SPID - that would pretty much close the case.

Re: Leaf or coil standard rear spring on GMC?
 

Unfortunately I do not have "original" glove box door as checking is not possible.

Re: Leaf or coil standard rear spring on GMC?
 

He’s a few pics of my sales book from 1970. Now Canada May be different than US built trucks. Clearly coils were standard here with leafs being the option.

Re: Leaf or coil standard rear spring on GMC?
 

My big block 1/2 ton '71 GMC is on coils. And nothing shows on the SPID.

Now there is another data point. LOL

Re: Leaf or coil standard rear spring on GMC?
 

Yep, and a good one - we now have some conflicting ones!
Anyone got a GMC data book from any of these years?
I can't say as I've ever laid eyes on a GMC-specific data book.

Re: Leaf or coil standard rear spring on GMC?
 

A 70 1/2 ton GMC that l parted out a few years ago. It was on coils- shows HD springs- could a 1/2 ton have heavier coils?

Re: Leaf or coil standard rear spring on GMC?
 

Yes, see the option sheet I attached above. Shows same code for heavy duty leafs and coils option.

Re: Leaf or coil standard rear spring on GMC?
 

Thanks- surprising the hd coils are higher GVW than the hd leaves

Re: Leaf or coil standard rear spring on GMC?
 

My 70 cst bb swb Canadian built Chevy is factory leaf spring truck, was used to haul camper, and the red and white 71 super sb swb Chevy is also a leaf spring truck. List on spid for both.

Re: Leaf or coil standard rear spring on GMC?
 

Those are front springs on the SPID you posted and not rears as this thread was relating to.

Re: Leaf or coil standard rear spring on GMC?
 

In Canada Chev and GMC 2wd were rear coils standard and leafs optional. Rear leaf in general up here are fairly rare. Longhorns of course always leaf but they were all really basically a 1 ton at heart.

Re: Leaf or coil standard rear spring on GMC?
 

Look on the left side- G50

Re: Leaf or coil standard rear spring on GMC?
 

So it is settled.....we are right after all.


...lol