I saw this in a thread and I figured it might get missed.

I'm thinking about doing a flush on the system. Is the cooling system on Vettes that crazy?? What are these tablets?? What do they do?

 

My 95 requires them I think they're supposed to "lubricate or seal" something not sure but my manual calls for them so I will always use them.

 

stop leak

 

gm pellets.its a combo of lube,stopleak,and coolant conditioner to stop electrolysis from the dissimilar metals.(aluminum heads on cast iron block).
you can get em at any gm dealer or parts store.just ask for gm pellets.
its a good idea to add a couple to fresh antifreeze when flushing.
put it this way. they dont hurt.
they are stop leak,and mobil 1 is oil.
nothing different about the colling system as far as flushing goes.
same as any other car,if you have a seep thats about to show up then flush the system,you will find it.
unless your having an issue,dont stir that pot imho.

 

I was thinking about doing it before winter. It was last done almost for years ago. Coolant still looks/reads good... Its the age that scares me.

 

I don't use them on either of my GM cars, no leaks or problems. They have been blamed for sludging DEXCOOL, I guess that's why GM stop recommending them.

Eric

 

Anybody else have sludging problems??? Thanks for the info.

 

read this- http://www.caddyinfo.com/howtosealantconfusion.htm

pretty much sums it up.did any c4 come with dexcool in it?
not that its bad,just that i never thought it was a good idea to switch from the green stuff to dexcool.
if you do you could very easily see some "sludging".

 

S0 is good ol Prestone fine?

 

Just crush the pellets and let them dissolve in your black coolant reservoir.

DO NOT put them into the overflow tank at the bottom of your nose. And don't freak out when they turn your coolant slightly darker. That's normal.

 

I seem to recall that GM issued a TSB a couple of years ago that discontined the use of the sealer tabs in LT1 systems using green coolant. Don't recall why but I think it had something to do with sludge buildup.

I think that 95 and 96 C4's use Dexcool so earlier cars need the ethlyene glycol (green) coolant. I have used Prestone for years and has worked well in everything. Use a 50-50 mix of coolant and distilled water in the final fill. That provides protection to about -37 degrees.

 

I would be interested in knowing whether or not there was a TSB issued on this. Anyone?

I also looked on CAC in their knowledge base and didn't see any TSB on this. I don't have a mygmnow member but do they list all applicable TSBs?

 

I dunno' but you could still get the radiator pellets from Cheverolet two years ago. That's when I purchased mine.

 

Yep I picked up a package last winter when I did my thermostat and throttlebody. The part number in the owners manual has been superceded, I'll look through my invoices to find the new one. Now they are tablets not pellets and come in a package of 5. They are the size of horse pills! You only need three tablets per system.

 

my local dealer had them in a carton on the counter last summer.
i will go check the tsb's and see what i can dig up.

yes,just use good ol green stuff mixed with distilled water.

ok-under this headingEX-COOL Engine Coolant Information #00-06-02-006A - (Feb 13, 2004)
i found this pellet info:
Cooling System Sealing Tablets (Seal Tabs) should not be used as a regular maintenance item after servicing an engine cooling system. Discoloration of coolant can occur if too many seal tabs have been inserted into the cooling system. This can occur if seal tabs are repeatedly used over the service life of a vehicle. Where appropriate, seal tabs may be used if diagnostics fail to repair a small leak in the cooling system.
When a condition appears in which seal tabs may be beneficial, a specific bulletin may be released describing their proper usage. After performing specific procedures outlining seal tab usage, install an appropriate identification label to indicate that the seal tabs have been installed. If seal tabs were installed in the cooling system during assembly, the recommended amount may be added if the cooling system is drained and refilled during a service event. The recommended number of seal tabs depends on the capacity of the cooling system. Use between 1 and 1-1/2 grams of seal tabs per liter of cooling system capacity.

what they are saying is dont add the things unless you changed the coolant.note thats for dex-cool and is from 2004 so is not c4 specific info.

but-(hope this isnt to long guys sorry) -check this one out:
INFO. ON DEX-COOL (TM) ENGINE COOLANT #53-62-02 - (Nov 13, 1995)
SUBJECT: INFORMATION ON DEX-COOL(TM) ENGINE COOLANT - INFORMATION ON BACKSERVICE

MODELS: 1994-95 PASSENGER CARS AND TRUCKS

A NEW EXTENDED-LIFE ENGINE COOLANT CALLED DEX-COOL(TM) IS CURRENTLY BEING USED IN ALL GENERAL MOTORS' VEHICLES (EXCLUDING CHEVROLET GEO AND SATURN). REFER TO BULLETIN 53-62-01 FOR GENERAL SERVICE INFORMATION.

**BACKSERVICE**

DEX-COOL(TM) MAY BE USED IN GENERAL MOTORS VEHICLES ORIGINALLY BUILT WITH CONVENTIONAL (GREEN) COOLANT WITH THE FOLLOWING CONSIDERATIONS:

* VEHICLES ELIGIBLE FOR BACKSERVICE ARE 1994 AND 1995 MODELS (EXCLUDING 1994 J BODY WITH 4 CYLINDER ENGINES).

* THE SERVICE INTERVAL FOR DEX-COOL(TM) INTRODUCED INTO AN OLDER MODEL VEHICLE ORIGINALLY BUILT WITH "GREEN" COOLANT WILL BE 2 YEARS/30,000 MILES (50 KM) (NOT 5 YEARS/100,000 MILES (160,000 KM)).

* ALL THE "GREEN" COOLANT MUST BE REMOVED FROM THE COOLING SYSTEM BY MEANS OF A SYSTEM FLUSH. THIS MAY BE ACCOMPLISHED WITH A WATER FLUSHING DEVICE OR A GMDE WATERLESS COOLANT CHANGER (USE A UNIT DEDICATED TO "GREEN" COOLANT, NOT DEX-COOL(TM)).

IMPORTANT: WHEN USING A GMDE WATERLESS COOLANT CHANGER, CONDUCT THE PROCEDURE TWICE, ONCE WITH WATER, AND ONCE WITH DEX-COOL(TM).

BACKSERVICE WITH DEX-COOL(TM) IS ADVOCATED BECAUSE OF ENHANCED WATER PUMP SEAL DURABILITY EXPERIENCED WITH THIS COOLANT.

no other mention of pellets in 92-96 y-body cars it the tsb search.
95 was the first year for dex-cool and some 95 c4s were mislabled needing a sticker change through a campaign.

thats iteresting input they sent out on the benefits of dex-cool.sounds like a good idea to use it.just make darn sure you get a good flush.one notice i read said dex-cool can be contaminated by the green stuff by merely using the same pour can.
sorry about the length of this post fellas

 

Good ol 50/50 it is! Thanks.

 

i would still recommend using regular antifreeze and distilled water with 2 gm pellets on an aluminum headed engine.
that is if your just gonna flush it yourself with some coolant flush and a hose.
the other option,and maybe best,is if you can hire someone with a flushing machine that you trust to do a thorough job and double flush it for a switch to dex-cool like gm recommended.
and then i would still add a couple pellets.

 

Thanks for the info!!! A little confused now. Is flushing the sysem that hard? I remember just hooking up a hose while the car was running and running water through the system until it was clean. I guess I better revisist this thought.

 

I see where you guys are saying 95's had dex. Mine was built in mid 95 it was built 05/95 and it has teh green stuff. Anyone know when they started using dex in teh 95's?

 

nah,dont worry about it.just get you a can of napa whatever cooling system flush and follow the destructions.
take your time.drain the system,refill it with water.warm it up,let it cool,drain the system...repeat.probly not a good idea on our engines to run it with cold water running through it.just use the fill,circulate,drain,refill method being careful not to add cold water to a warm block.
use the air purge valves at the front of the intake to get all the air out too.
i would figure on it being a good 12 pack job for 2 guys.