Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

Hello,

I've owned my truck for just a few months and took it to my mechanic to have the fluids checked. Among other things, the radiator leaks. Since I'm eager to learn about and work on the truck myself, I'm going to do the replacement with my hubby's supervision.

I'm reading and tagging the radiator replacement threads for reference, but I'd like input as well. My husband's knowledge is mostly around Jeeps and his fancy-schmancy 1973 overlanding Blazer, so his vehicles serve a different purpose.

My truck is a 1977 GMC Sierra Classic 3/4 ton longbed 4x4, 400 small block. I mostly use her for daily driving in suburban areas when I don't want to drive my Kia. ;)

But she was purchased for towing trailers and especially for a long-haul tow for a move from So Cal to Portland, Or (once my house sells...know anyone who wants to move to Trabuco Canyon, CA???). And I want to use her as a heavy duty truck when needed (as opposed to, say, offroading or a show vehicle).

I waffle between restoration/preservation and upgrading to the newer, more efficient designs. Then again, it's a lifted truck, so it's already not fully stock.
-- What are good options for original-style radiators?
-- What are good options for efficient newer tech?
-- Cost is not my main concern (I'm redirecting my wine and clothes budget).
-- Are there vendors on our site you would recommend?

And, finally, any installation tips specific to this year/model?

Thanks!

Michelle

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

A radiator replacement is a good starting point for learning. It's just complex enough that you get to deal with a bunch of the headaches like difficult bolts to reach, hoses that don't come off, and other stuff that are all "normal" when working on cars. But it's not too difficult and daunting, like an engine overhaul.

As for restoration vs upgrading, my personal philosophy is that it only matters in two areas. The first and obvious is a show truck. The second is any place it SHOWS. I don't want different headlights, or a different grill, or a different set of heater controls or gauges. I want OEM, because it shows. But the radiator doesn't show. Ain't nobody going to pop the hood on an old rustbucket, with three diffent colored quarterpanels, and say "Oh, it's got the original radiator. Nice!". Unless it's a show truck, nobody is going to judge you because your radiator isn't OEM.

(I'm not implying your truck is an old rustbucket, or is several different colors, but you get my meaning.)

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

The last couple if radiators that I have replaced in theses trucks were replaced with spectra premium radiators from rock auto. They are aluminum, with plastic side tanks, but I haven't had any problems with leaks, and they cool way better than the ones they replaced. I hate draining antifreeze, so when I have too, I replace all the hoses, the water pump, and thermostat. The parts are cheap for these old trucks.

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

Just bought one, was a shade tall for mine.

But the quality was good.

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

@Wilkin250r: Thanks for that philosophy. That actually really helps to frame the issue. Yeah, it's not a rust bucket, but she's got some extra colors for sure. Thanks for the encouragement too! I replaced a fuel vent hose, so of course now I think I can take on bigger projects. :lol:

@Jaysonb: Thanks for the resource. I found my truck on the Rock Auto site and it listed two options (three, but I'm ignoring the one that says w/o AC). Other than measuring and matching my current radiator's dimensions, are these two essentially the same thing (see image)?

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

X2 on Spectra aluminum/plastic radiator. I put one in my 83 C20 w/AC 454 and it cools fine - even in 115 degree Arizona desert heat. I bought mine online from Autozone with 20% off and free shipping delivered to my door. I have a thread on this somewhere on this forum.

I separated the brass/copper from the steel on the old radiator and sold it at the local scrap yard for I think about $30, so my net cost on the new radiator was less than $100.

If you are concerned about originality you will likely not find an OEM radiator that still has any life in it, and rebuilding one correctly will cost a lot of money. I now think plastic/aluminum is better than copper/brass.

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

Yep, yours is one I'm following already. (http://67-72chevytrucks.com/vboard/s...light=radiator)

Thanks for the additional vote on the RockAuto equipment.

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

I looked over the options. Went to a salvage yard and got an original copper and brass one for under 100 bucks,got it out in 15 min. It was guaranteed. Bolted right up, perfect fit. New C/B was like 400 to 600 bucks.

Re: Seeking input on radiator replacement for 1977 GMC 3/4 Longbed
 

I guess a lot of your choice has to do with the climate where you live. In HotZona I have never had more than a few years without copper/brass leaks. I just replaced the aluminum/plastic radiator in my 2002 Cavalier with 146,000 miles on it (the original radiator) and that was because it was clogged up, not leaking. The AC Delco replacement for that radiator was right about $100 delivered from Rock Auto. I think I got about $8 for the aluminum scrap from the original radiator.:lol: