Brother Al
I'm Awesome
MLX10, sadly, it could very likely be a head gasket going south. There are no signs of water/af in the oil or trans fluid, right?
Oil Cooler... never said deleting it will kill an engine, and yes, millions of vehicles never came with an oil cooler. Deleting it wont cause you to overheat, or make your muffler bearings cook off your blinker fluid... An oil cooler serves a good purpose... extends your oil life, as well as maintain the oil's ability to fully lubricate and cool your bearings when you are working an engine hard. My take on tearing out an otherwise useful oil cooler is comparable to someone tearing out their efi and putting on a carb on because they have an injector problem.
Why remove it when you can just fix it?
Tinfoil Hat... yep, the "composite parts" includes those cheesy GM gaskets, I shouldve written it better... but having replaced few cracked intake manifolds on GM 3.8's... Yes, AF does indeed flow through the plastic Series II 3.8 intake to the throttle body ...and probably the other FWD V6 engines too. On a Series II 3.8, the EGR port goes right through the intake near the throttle body coolant passages in this same area. I would guess the GM engineers musta thought that the AF would sufficiently cool the area, but it slowly cooks the plastic, causing it to crack/melt/fail, whi h readilly allows AF to leak/get pulled directly into the engine. Ive also had to deal with GM's GMs stupid 4.3L Vortec I CPI design... yeah, not a fan of composites.
As for Dex-Cool, I didnt realize GM added some stop leak tabs seperately. My experiences with Dex-Cool are not good. As Id said earlier, it was designed to work in sealed systems, bit when exposed to any kind of air, it readily decomposes and sludges up. Every vehicle Ive had with Dex-Cool has had cooling system problems and sludge. My '03 Blazer had an extended GM warranty, so I left the Dex-Cool in the system, per the dealer's insistance that it was "fine". At a bit before 70K, I noticed I was running hotter than normal... I didnt see any signs of premature oil breakdown (Mobil 1 since 30K) & the AF was full... Dealer said "water pump failure"... This was just before the warranty expired. Not long after it did expire, I lost my heat... I discovered I had a clogged heater core. I personally did a thorough ***** of the system and got a lot of gunk out, then replaced the radiator, thermostat, overflow jug, hoses, and heater core... everything was coated in sludge. Prestone Green went in. My Wife's '07 Trailblazer got the same right after it passed its warranty period. The Wife's 2015 Acadia is a lease, (not buying a "new" vehicle again.) On top of all that, GM had a huge Class Action Lawsuit filed against it and they Lost in 2008. I was part of it, but never got a dime because GM appealed and their bankruptcy killed off whatever settlement money I should have received.
http://www.girardgibbs.com/dexcool/
Sorry for the hijack MLX10... and again, your truck never had Dex-Cool, so if it does now, flush it out really good and put in something better than Dex-Cool (OAT) and use Peak (IAT), or maybe an HOAT-type Coolant (Hybrid Organic Acid Technology), or even Amsoil's AF types (Poly Organic Acid Tech- IIRC its also silicate free) .. just my 50 cents.
Oil Cooler... never said deleting it will kill an engine, and yes, millions of vehicles never came with an oil cooler. Deleting it wont cause you to overheat, or make your muffler bearings cook off your blinker fluid... An oil cooler serves a good purpose... extends your oil life, as well as maintain the oil's ability to fully lubricate and cool your bearings when you are working an engine hard. My take on tearing out an otherwise useful oil cooler is comparable to someone tearing out their efi and putting on a carb on because they have an injector problem.
Why remove it when you can just fix it?
Tinfoil Hat... yep, the "composite parts" includes those cheesy GM gaskets, I shouldve written it better... but having replaced few cracked intake manifolds on GM 3.8's... Yes, AF does indeed flow through the plastic Series II 3.8 intake to the throttle body ...and probably the other FWD V6 engines too. On a Series II 3.8, the EGR port goes right through the intake near the throttle body coolant passages in this same area. I would guess the GM engineers musta thought that the AF would sufficiently cool the area, but it slowly cooks the plastic, causing it to crack/melt/fail, whi h readilly allows AF to leak/get pulled directly into the engine. Ive also had to deal with GM's GMs stupid 4.3L Vortec I CPI design... yeah, not a fan of composites.
As for Dex-Cool, I didnt realize GM added some stop leak tabs seperately. My experiences with Dex-Cool are not good. As Id said earlier, it was designed to work in sealed systems, bit when exposed to any kind of air, it readily decomposes and sludges up. Every vehicle Ive had with Dex-Cool has had cooling system problems and sludge. My '03 Blazer had an extended GM warranty, so I left the Dex-Cool in the system, per the dealer's insistance that it was "fine". At a bit before 70K, I noticed I was running hotter than normal... I didnt see any signs of premature oil breakdown (Mobil 1 since 30K) & the AF was full... Dealer said "water pump failure"... This was just before the warranty expired. Not long after it did expire, I lost my heat... I discovered I had a clogged heater core. I personally did a thorough ***** of the system and got a lot of gunk out, then replaced the radiator, thermostat, overflow jug, hoses, and heater core... everything was coated in sludge. Prestone Green went in. My Wife's '07 Trailblazer got the same right after it passed its warranty period. The Wife's 2015 Acadia is a lease, (not buying a "new" vehicle again.) On top of all that, GM had a huge Class Action Lawsuit filed against it and they Lost in 2008. I was part of it, but never got a dime because GM appealed and their bankruptcy killed off whatever settlement money I should have received.
http://www.girardgibbs.com/dexcool/
Sorry for the hijack MLX10... and again, your truck never had Dex-Cool, so if it does now, flush it out really good and put in something better than Dex-Cool (OAT) and use Peak (IAT), or maybe an HOAT-type Coolant (Hybrid Organic Acid Technology), or even Amsoil's AF types (Poly Organic Acid Tech- IIRC its also silicate free) .. just my 50 cents.