1979 6.2 k5

[dixiepc]

I'm getting ready to put a 6.2 in a 1979 K5 that I just bought. The radiator for the 6.2 is bigger like one for a 454. The 82' and up radiator supports have provisions for the shorter radiator or the longer one. But this 79' radiator support doesn't have these provisions. Did they ever have the longer radiators in 79' trucks?

[V30 mongo]

Quite a few changes were done for the 81/82 model years. The cab floor pan was changed, the dash, and the complete front end. The radiator for the diesel is big, really big. The newer front radiator mount should have the mounting holes. I guess you can install a diesel in the older truck, but it will take as lot of work. There is more than just the cooling system. Diesels require two batteries, the starter is also big, along with the wires. The fuel system must have a return system or you will have air in the fuel problems..

[dixiepc]

It won't be a big job at all. The return lines are already there. The engine with bolt right in. And the batteries are no problem.

I don't really think that the cooling will be a problem as they put these in Toyota Land Cruisers and you can't put a very big radiator in those. I just wondered what they did in 79' when they used a big block.

[crashz]

Both of my 83's and my 87 have the same 6.2 radiators, which are big in outer dimensions, but I think they are either 2 or 3 core radiators.

I've heard of people using a smaller, 4 or 5 core radiator in place, and actually improving cooling. Totally internet hearsay though and I have no proof of that working.

[Edahall]

The large size radiator is needed for towing. These engines put out a LOT of heat when towing heavy loads.

[Corts60]

Originally Posted by dixiepc

I'm getting ready to put a 6.2 in a 1979 K5 that I just bought. The radiator for the 6.2 is bigger like one for a 454. The 82' and up radiator supports have provisions for the shorter radiator or the longer one. But this 79' radiator support doesn't have these provisions. Did they ever have the longer radiators in 79' trucks?

To answer your question, yes, but only if it was a diesel truck. My '78 factory diesel has a bigger radiator than even the 454 powered trucks. There is a tranny cooler on the driver side tank, and an oil cooler on the passenger side tank. Of course the chances of you finding a factory diesel truck core support is going to be very hard. But, all in all, it can be done. If you need, I can take a picture for you.

[dixiepc]

A picture would be great.

[Corts60]

Hope these help ya buddy:

[dixiepc]

Thanks for the pictures. It's hard to tell from the pictures but is that radiator core 34"?

I've wanted a truck with a 5.7 Diesel for a long but I'm afraid that parts might be too hard to find. They get some great mileage.

[ray_mcavoy]

Originally Posted by Corts60

To answer your question, yes, but only if it was a diesel truck. My '78 factory diesel has a bigger radiator than even the 454 powered trucks. There is a tranny cooler on the driver side tank, and an oil cooler on the passenger side tank. Of course the chances of you finding a factory diesel truck core support is going to be very hard. But, all in all, it can be done. If you need, I can take a picture for you.

Interesting ... with the exception of the oil cooler & heater hose return, that doesn't look a whole lot different than the radiator in Dad's '77 with a 400 small block.
Did 400's use the same size radiator as diesels? I always thought they were the same as 454 radiators ???







For reference, this radiator has a 28-1/4" wide x 19" tall core. I know the 80's 6.2L diesel radiators are even wider than this.

[dixiepc]

6.2's and 6.5's had radiators with 34" wide cores. Some were 17" tall and some were 19".

[Corts60]

That does look pretty similar to the 400 radiator. Maybe they were the same. Yes, mine is a 34" core.

[SamsAutoParts73-87]

Aux battery trays for 73-80 are not a hard item to find, even LMC carries them, and they can be had used as well.
-Sam

[dixiepc]

Got no problem with that part. Just trying to figure out a longer radiator on a 79' core support. Or if the 28" radiator core will cool the 6.2.

I already run a couple of 6.2's so I'm very fimilar with them. Unless your towing or pulling a steep grade they actually seem to put out less heat than a gasser.

[Edahall]

Yeah, you don't need much radiator to cool these engines if you're never intending to tow. They produce very little heat at idle compared to a gasser. However, they heat up fast towing huge loads and slogging up a hill.

[hatzie]

Radiators are usually measured to the ends of the core not the tanks.
I used a 4 row 29" x 19" core radiator in my '76. That's prolly 34" or 35" to the ends of the tanks. The problem you'll run into is the HD radiators were taller. I went from something like 16" 3 row to 19" 4 row. The top support is different depending on the core height.

I used a power steering cooler to keep the hydroboost happy.
I didn't get a radiator oil cooler. My oil cooler is an external B&M plate type unit similar to the one GM used on the T400 chassis diesels with modified hybrid cooler hoses (stock on the block married to AN braided from the cooler). Yes. I had to cut the core support to route the cooler hoses through.
The nasty part, for me, was fabbing mounts for the aftermarket parallel flow condenser and the oil coolers so it looked decent. It can be done without looking ghetto or blocking airflow.

I have an NV4500 so the tranny doesn't get a cooler.

[dixiepc]

Originally Posted by hatzie

Radiators are usually measured to the ends of the core not the tanks.
I used a 4 row 29" x 19" core radiator in my '76. That's prolly 34" or 35" to the ends of the tanks. The problem you'll run into is the HD radiators were taller. I went from something like 16" 3 row to 19" 4 row. The top support is different depending on the core height.

I used a power steering cooler to keep the hydroboost happy.
I didn't get a radiator oil cooler. My oil cooler is an external B&M plate type unit similar to the one GM used on the T400 chassis diesels with modified hybrid cooler hoses (stock on the block married to AN braided from the cooler). Yes. I had to cut the core support to route the cooler hoses through.
The nasty part, for me, was fabbing mounts for the aftermarket parallel flow condenser and the oil coolers so it looked decent. It can be done without looking ghetto or blocking airflow.

I have an NV4500 so the tranny doesn't get a cooler.

Man do you have a build thread on your 76'? I've got an 84' that I want to put a NV4500 in. Having trouble finding a pedal setup for hydraulic clutch with hydroboost.