[FirstDiesel]

Eric


Since we're doing non-Dmax questions here thought I'd ask you what you think about the 4.3 engine with the Dexcool??





I have a 2001 S10 with about 65k on it. It's my work truck and I need to make it last at least as long as the S10 with the 2.8 it replaced. That was 315K and 10 years.





I'm worried about this Dexcool thing and the lawsuit about it. I'm still on the original load of coolant and was planning on replacing it at 100k which will be between 3 and 4 years of it's life.





My questions are as follows:





1. The other day I noticed a little build up of something around the cap so I opened it. The level was full but there was a crusty build up on the ends of the cap. I cleaned it all off and got a new cap in case the cap was allowing air into the system.


Is there anything else I should be doing, or should I be worried about a problem?





2. When it comes time to change the antifreeze I would normally have drained the fluid out and run the engine with a hose in it for a long time allowing a little of the water to drain out the drain plug to flush out the system completely. I then would have run some radiaot flush in the system and flushed it out the same way. I then would have refilled the system with fresh antifreeze.





Is this an okay method to use with the Dexcool?? Is there a problem if I don't get all the tap water out of the system before I add the Dexcool?? Should I even be refilling with Dexcool or go with regular antifreeze. What is the best way to try to completely drain this system??





Thanks for you input

 

[dmaxalliTech]

Larry, it is now time to do a flush. Its ok to use the Dexcool, just dont let the level get low, its detrimental to the cooling system. When the air mixes with it for some reason it turns to crap. I only see it in the s/t trucks so beats me why. If you let it go to long, you will need to acid flush it, there is a tsb that outlines the flush process, takes about 4 hours to do. The acid that you use is potent enough to come with a neutralizer to avoid eating the aluminum!! It also suggests replacement of the t-stat and rad cap. I would pull the block plugs, kind of a bear to get to, but do-able, I use a 9/16 chrome swivel socket on a long ext. drain the block, rad and remove the heater hoses that you can get to. Also remove the tstat and shoove the hose in everything you unhook untill you get clear water all around. I run the engine even with hoses unhooked to use the water pump as a pressure clean for the block where its hard to flush. let everything drain good and refill with 50/50 mix of coolant. You can go green or back to dex-cool, just dont let it get to the point of sludge, some extreme cases will require replacement of radiator and heater core as they will not clean up.

 

[FirstDiesel]

Eric





Are you saying I need to do all those flush things NOW or if I had a problem and used the acid?? Sounds like an awful bunch of nasty work under the hood of that engine. I still haven't even seen the sparkplugs under there.





Replacing the thermostat now too??

 

[dmaxalliTech]

Larry, sorry about the confusion, but if you catch it now, which by the way it sounds, isnt a big problem, Just do a good drain and fill and you should be ok. You may also choose to use a quality additive in your cooling system. The acid flush is not necc unless you have some major sludge build up going on..

 

[FirstDiesel]

Thanks Eric





I'll drain it out and refill it. Is it good enough to just dump what comes out without running any water through it.





I'm very paranoid about this new coolant and the problems reported about it. If I flush the engine with water I will not get all the water out and I'm wondering about "tap" water mixing with the coolant. Is this a problem??





What kind of additive do you recommend that is compatible with the Dexcool. I always added Prestone Anti-Rust/Water Pump lube to my trucks with the regular coolant.

 

[dmaxalliTech]

"tap" water is acceptable, thats all that we use in the shop. If you read the jug, they want purified water. Unless your jbplock, its not needed

. The Prestone should be ok, ,just read the label and make sure its compatible. At this point, a drain and refill should be ok.

 

[FirstDiesel]

Thanks Eric