View Single Post
Old 12-27-2019, 07:28 PM   #5
hatzie
Moderator
 
hatzie's Avatar
 
Join Date: Oct 2008
Location: Wentworth, NH
Posts: 5,022
Re: Pulled The Trigger

Quote:
Originally Posted by Ironhorse View Post
Changed out the Dex-cool in our '99 Tahoe with the 5.7 when had to do the intake gasket replacement. That was nearly 90,000 miles back and never a problem. Only thing I did was put a large printed label on the radiator stating "Converted to Ethylene-glycol" Had been very pleased with the results and never had it turn to jelly.
It's only the real early Dex Cool formulations that turned to jello but the reputation lives on...
I'd guess that 95% or more of it was people topping off the new OAT Dex Cool systems with "green" IAT Silicate coolants that were in common use at the time.

Converting from OAT to IAT coolant is similar to moving from synthetic oil back to dinosaur squeezins or bolting a carb onto your TBI engine.
It'll work but there's a reason GM started using DexCool, Synthetic oil, and electronic fuel injection... it wasn't to have something exotic in the cooling systems and crankcases and even the early TBI systems really do perform better on less fuel.
__________________
1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.

Last edited by hatzie; 01-10-2020 at 11:13 AM.
hatzie is offline   Reply With Quote