6.5TD Radiator Question

[trbankii]

Had searched and added this question to the end of another radiator question - didn't realize it was in the 6.2 forum until now...

Ok, looks like I'm in the market for a radiator... This morning there was a puddle under the driver's side front corner. Pulling the upper shroud this evening showed copper patina colored corrosion down both ends of the core where it meets the side caps and putting a pressure tester on showed at least one actual hole on the driver's side.

Looking at RockAuto and Discount Radiator, I'm a bit confused by the options. The more expensive ones are the ones that say WITH engine oil cooler... Does that mean with an engine oil cooler built into the radiator? I have an engine oil cooler, but it is separate. If they are talking about trucks with the SEPARATE oil cooler, why is that model more expensive?

Also, Discount Radiator doesn't make any mention of transmission oil coolers - with a manual, I don't need one... At RockAuto three of them have transmission oil coolers and two of them make no mention either way...

Just want to make sure I order the correct part... Many thanks!

[Robyn]

I would go with one of two choices.
The later model radiator for the 1 ton duallies is an aluminum core with pastic tanks.
The HD units had the engine oil coolers seperate but still had the tranny coolers.
The local radiator specialists tell me that the HD GM units are hard to beat and will actually perform as good or better than the all aluminum units that are sold aftermarket.
This is due to the fact that the plastic tanks with the gasket can allow for expansion and contraction without cracking.

The Burb HD units had both engine and tranny coolers in the tanks.

Im not sure if you can get one without any coolers though.
Check with the GM parts folks and there may well be a HD unit for a 1 ton that had a stick shift and remote engine coolers so you may find just what you need.

The newer units should fit your chassis with minimal bother.

Hope this helps

Robyn

[trbankii]

Thanks, Robyn. I think that was the information I was looking for - that there were ones with tranny and engine oil coolers built into the radiator. The factory service manual just isn't clear about such options.

I just need the radiator without any coolers. DiscountRadiators has one like that for $250 and change. RockAuto has a Spectra Premium without aux. coolers for $390 and change. Neither really gives the construction - aluminum and plastic or traditional... I think I'm going to go with the DiscountRadiators one for the time being due to some other factors of not wanting to spend a lot right now.

Thanks for the help!

[HH]

I installed an SFI rad, it came with both trans and oil cooler connetions, even though I not use them. It has plastic tanks and AL core. It has been fine so far, but I've only towed small boats and car trailers in the last two years. I have a seperate engine oil cooler, tube & fin style.

[trbankii]

Well, for the moment I'm going the ghetto route - some JB weld stuck into the offending area of the radiator. I had it scheduled in for the annual inspection on Tuesday and don't want to have to cancel that. Hopefully the epoxy will stick for at least a little while so that I can get it inspected and spend some more time gathering parts. I'm not going to be working it hard until the new radiator is in there.

It's a manual transmission, so no need for a tranny cooler. And I do have the separate engine oil cooler, so no need for that. At first, I was reading the listings as meaning trucks with engine oil coolers or trucks without - not that the engine oil cooler was built into the radiator.

[trbankii]

Another thing...

As Jim put in the 1999 Feature Articles book (also in the first 6.5TD book) in his article on radiators, clean those things out once in awhile!

I was amazed at all the dirt, leaf matter, and other assorted garbage in the fins and trapped between the radiator and a/c condensing unit... The PO must have been a sheep farmer for all the wooly stuff caught in there!

Granted, that was probably the first it has been cleaned out in the past fourteen years, but I can see a thorough cleaning every three years being well worth it.

[trbankii]

Just wanted to say that the radiator came from DiscountRadiators today - a Spectra Premium - plastic tanks with an aluminum core. So saved $140 over what RockAuto wanted for the same thing - $250 vs. $390. I did get two new hoses from RockAuto. Hopefully I can find some time to get it in the truck in the next few days.

[More Power]

New 6.5 & Duramax aluminum radiators from GM are $600-700. I wonder if there's any difference between what GM sells and the aftermarket varieties?

The number of core tubes and total wetted surface area are what determine the radiator's heat rejection capability. Some aluminum radiators (not necessarily these 6.5 versions) use fewer, but larger tubes - more of a flattened oval in cross section. It's all about wetted surface area. Copper/brass rads use more, but smaller oval-shaped cross tubes.

The last 6.5 copper/brass rad I had rebuilt used a 5-row core. It had functioned normally, and without any leaks or noticeable solder bloom (when looking down into the radiator with the cap removed) for more than 6 years and 200K+ miles, without a flush/fill.... But, I had used the long-life Havoline Dex-Cool when the system first went together. :)

Jim

[trbankii]

I unpacked it when it came in to check for any shipping damage, but I'll have to take a closer look at it tomorrow evening. I can try to post up some pictures for comparison.

My initial thought was to have the original rodded and fixed up, but it is just too far gone.

[tommac95]

OK while you're at it , give the system a good flush with pure water [distilled,de-ionized, or reverse-osmosis, from the supermarket] and then fill with good antifreeze.

[Robyn]

If you dont mind the cost go with CAT ELC.
This is premixed and you dont add anything to it. Also dont ever mix the standard stuff wth it or its crap.

I run this stuff in My 500 Cat in the Western Star, Its a really nice red color.