Coolant Choices, Dex vs Prestone vs Peak 10x

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Dec 7, 2012
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I'm really splitting hairs here... reading different opinions on coolant and not sure which way I want to go.

Swapping a 2007 LQ4 6.0 into my 2005 Tahoe. Tahoe had Dex-Cool, but has been drained and filled with Prestone All Vehicles (yellow jug/lime green-yellow color) a couple of times -- reserviour looks mostly yellow-ish. The LQ4 had Dex-Cool and there's probably still some in the block.

I am confused as I am reading that the Prestone is essentially a Dex-Clone, or something about 2EHA... I'm just a little lost. I do have a couple of new Jugs of Peak 10x coolant sealed.

My options are:

1. Blow out heater core, rear heat lines + rear heater core and radiator (best I can) of the current coolant and re-fill with Dex-Cool.
2. Re-fill with Prestone All Vehicles (what was last used)
3. Re-fill with Peak 10x

What one would you use? I used to think the Peak 10x was the same as the Prestone All Vehicles.

Maybe I'm overthinking this?
 
I have used Dexcool in my 6.0 LY6 for the last 15 years, but for your situation I go with the Prestone 10 year all vehicles. I wouldn’t worry about the Dexcool in the block. They are compatible. If you are worried, run water through the system once the engine is installed, then add the new coolant.

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I have seen multiple times that mixing Dexcool and Prestone AMAM can lead to gelling.

If you don't have more Prestone AMAM, I would flush and fill with Peak 10x.
 
I have seen multiple times that mixing Dexcool and Prestone AMAM can lead to gelling.

If you don't have more Prestone AMAM, I would flush and fill with Peak 10x.
Hmmm... maybe that explains me having to flush my heater core back in July/August. I drained out the Dex-Cool and filled with Prestone AMAM under the impression they mixed fine.

New motor -- might be a good time to flush the entire system to clear and then choose my drink after its clean. Maybe I just will go wtih Dex.
 
Flushed my 2001 Buick LeSabre a while back and refilled with the Peak 10x. I'm pretty sure it's fine and no worse or better than the Dex....

Key is to flush the system...
 
I have seen multiple times that mixing Dexcool and Prestone AMAM can lead to gelling.

If you don't have more Prestone AMAM, I would flush and fill with Peak 10x.
Not sure that's true anymore-Ford is actually recommending Prestone AMAM with Corguard for the vehicles that originally came with Specialty Orange (which is Dexcool). I had a company 2018 Transit 250 that had coolant leaks (that Ford couldn't/wouldn't repair)-I put in Orange, then the dealer put in Gold (which is Prestone), by the end I was dumping in the used Dexcool from the Express in my sig! Never hurt anything, there was so much Dex in there by the time the company dumped it (125K) the degas tank was red!
 
Think I am going to use the Peak 10x I have on hand. Seems like a flush out and refill with it should yield adequate results.

I may have some left over prestone as well, which in that case, I would assume should also be just fine.
 
Think I am going to use the Peak 10x I have on hand. Seems like a flush out and refill with it should yield adequate results....
I like the call on 10X here. It will mix with whatever there now, or flush the system will work too. The latter assures longer service interval if that's a consideration.

If I was choosing one AF for all my vehicles, 10X concentrate it would be.
 
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I like the call on 10X here. It will mix with whatever there now, or flush the system will work too. The latter assures longer service interval if that's a consideration.

If I was choosing one AF for all my vehicles, 10X concentrate it would be.
100% agree! Plus, the OP has it on-hand. Been running it in my Buick now and it makes changes so much easier with 'one" coolant. Thanks!
 
Agree with both of you. I know I'm splitting hairs but figured with the motor job coming up, lets do all right! But I don't think I can go wrong with the 10x!

Thanks.
 
Think I am going to use the Peak 10x I have on hand. Seems like a flush out and refill with it should yield adequate results.

I may have some left over prestone as well, which in that case, I would assume should also be just fine.
Good choice! I've been using Peak 10x in my Cad and Honda for a few years, and put it in the Toyota last summer. One for all.
 
I have seen multiple times that mixing Dexcool and Prestone AMAM can lead to gelling.

If you don't have more Prestone AMAM, I would flush and fill with Peak 10x.
The only difference that I see between Prestone AMAM and Dexcool (besides color) is that the Prestone uses 2-EHA sodium salt while I believe that the original Dexcool used 2-EHA potassium salt. Whether that difference would make them incompatible with each other....I have no idea?
 
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Prestone 10 year is now OAT, just like DexCool, with slightly different additives (as mentioned above). It is a fantastic product, use with confidence.
 
My 98 Chevy with the old school engine and angled radiator neck still has an all original dexcool system.

id run dexcool, or else get the Prestone American orange. If you’re really going to go out of your way to get something different, I’d go with JD Cool Gard II.
 
I'm really splitting hairs here... reading different opinions on coolant and not sure which way I want to go.

Swapping a 2007 LQ4 6.0 into my 2005 Tahoe. Tahoe had Dex-Cool, but has been drained and filled with Prestone All Vehicles (yellow jug/lime green-yellow color) a couple of times -- reserviour looks mostly yellow-ish. The LQ4 had Dex-Cool and there's probably still some in the block.

I am confused as I am reading that the Prestone is essentially a Dex-Clone, or something about 2EHA... I'm just a little lost. I do have a couple of new Jugs of Peak 10x coolant sealed.

My options are:

1. Blow out heater core, rear heat lines + rear heater core and radiator (best I can) of the current coolant and re-fill with Dex-Cool.
2. Re-fill with Prestone All Vehicles (what was last used)
3. Re-fill with Peak 10x

What one would you use? I used to think the Peak 10x was the same as the Prestone All Vehicles.

Maybe I'm overthinking this?
2-EHA Is the boogeyman that really never was. The prestone is just fine.
This is a topic stemming from issues GM had 30 years ago that were blown all out of proportion and not necessarily widely understood.
 
I prefer Peak Universal 10X whatever they call it this week. Thing is I can’t use it in my car. So I have Dexcool from the dealer for that. But everything else gets the Peak.
 
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