How-to properly clean the cooling stack in a Duramax truck - Mechanics Minute

Your Duramax truck run hot in the summer months? We are highlighting a common issue this week with cleaning the cooling system "stack" The stack refers to the radiator, intercooler, air conditioning condenser and the transmission cooler mounted behind the grill.
As the truck is driven, overtime road debris, bugs, oils and tar and lots of other debris will lodge into the cooling fins of these coolers and restrict air flow. If air can not get through the coolers, cooling capacity is greatly reduced. Here we cover the basics on cleaning those fins.
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[@shdwwzrd69]

I actually did mine in the truck took intercooler out and got a pivot tip for pressure washer so I could clean straight on and didn't bent any fins but cleaned it up nicely I used purple power and simple green

[@MrDynafxdc]

That's exactly why I have always run a bug and pebble screen in front of my grill. Eleven years old on my duramax and clean as a whistle.

[@jayunitcooper]

is there a kit you can buy or did you just make it yourself

[@abndarwesh8514]

What is the name of this liquid that you used before washing with water

[@xIkkito]

there was alot of rst dirt between the fences

[@stevewaclo167]

Thanks for the video! Pulling the stack is more than I feel comfortable with and since I have a PWer, how you feel about pushing the dirt through from the front with everything in place? Big compromise but better than nothing?

[@merchantautomotive]

Anything will be better than nothing when cleaning it. Power washer can cause more damage than good if not careful is all. You want to be sure that you are not bending over any of the fins with the water pressure. Most of the build up is going to be between the radiator and intercooler, which of course is the hardest place to access to clean with out taking it apart

[@stevewaclo167]

@@merchantautomotive Thanks! PO installed an attractive Lund grill insert but it only has narrow, vertical slits for airflow 😟. My CA LB7 has an EGR cooler, like the LLY, and it’s my understanding, GMC did nothing to upgrade the cooling system.External oil cooler seems the way to go, but $$$.

[@2015_Rubicnn]

@@stevewaclo167 are you sure your LB7 has an egr cooler? I'm pretty sure the LLY was the first for that and a catalytic converter.

[@stevewaclo167]

@@2015_Rubicnn I have an ‘03 California LB7 which indeed has a cat and EGR.

[@2015_Rubicnn]

@@stevewaclo167 Well that is interesting....I believe 01 was the only year then that did not have a cat or EGR. I assumed they all didn't until 04.5. The RPO code in the glove box would dictate whether it was Cali or Federal emissions. 👍

[@kw3856]

you care to make a video about flushing 04 duramax?

[@merchantautomotive]

Keith, what system would you be interested in seeing a video on? The cooling system?

[@user-sn6ug8fi5m]

😎👍

[@tamilarasupalaniappan615]

what was used for cleaning radiator fins ?

[@FeenixRyzing]

Looked like Purple Power or Super Clean

[@stebensbobby]

I thought preasure washers can damage the fins

[@doodskie999]

Not if you angle it properly and not use the pointed stream

[@merchantautomotive]

use a wide fan pattern and be sure to spray straight on and not off to the side

[@aldotavolozzi2650]

Ciao ragazzi qualcuno ha mai avuto un sintomo simile io in poche parole avverto che superati i 130km/h solo tale velocità sale un cm il livello della temperatura del acqua 2 anni fa cambiai il radiatore post un piccolo tamponamento, non vorrei Mel avessero messo cinese, la guarnizione della testata non é bruciata non ho problemi né di ebollizione nella vaschetta stappandola né fumo bianco né poltiglia dovuta a mischiarsi di olio e liquidi, avete casi simili, grazie attendo info.
Quando scendo sotto i 130km/h la temperatura torna normale a 90°
Valvola termostati a cambiata

[@mikewinterhalt3024]

Why is it in every other vehicle it's called a radiator but here because it's a diesel it's called a cooling stack?

[@ericmerchant3646]

It’s still a radiator here too, but the intercooler and radiator bolt together, and the condenser right in front of that. It’s all “stacked” together, hence the slang term. In this case, you want to clean all of them, or the whole “stack” not just the radiator

[@mikewinterhalt3024]

@@ericmerchant3646 Got it. Thanks.👍🏻