Impala Forums banner

Antifreeze use

4K views 21 replies 7 participants last post by  luckydriver 
#1 · (Edited)
Has anyone here at all with the 3.6 had antifreeze loss issues? GM can't find a leak on mine and it passes their pressure tests but my surge tank level steadily declines and 2 separate analysis on my oil showed trace amounts of glycol. The past 3 analysis I have done show none however the loss continues. No visual on the car either... both myself and the dealership have looked. They won't pull plugs but I think i will i guess. I added about a quart of antifreeze now since I noticed this.. probably 8000 mile window of time and at just over 40000 miles on the car.

Just seeing if I am alone with this or if others have had problems.
 
#2 ·
on the wife's 2011 cruze with the 1.4 turbo we had a water block off the drivers side of the heads faile. then we also found out after having the dealer check that we were overfilling the reservoir jug due to a lack of markings on the jug for where the full cold line is...it was pushing out the extra through the top overflow hole.

any chance this is your issue? have you checked the water pump for leaks? is the oil clean or milky?
 
#5 ·
The oil stays clean in appearance and I only found glycol by analysis only. It increased on one oil change from a non reportable level to a reportable (still trace) . This last oil change I have tested it 3 times in around 3000 miles and it's been 0 every time but the big level continues to drop. The jug in these cars is pretty simple if you look at one and the full line is seam in the tank. It went from that to almost empty which is a quart or a little better. The dealer said it met spec on the pressure test which is something 1 psi loss per hour so it makes it a pain to find.

Probably something retarded like my old Caprice years ago that had a crack in the intake port on the passenger side head. It only leaked with the right conditions present and otherwise stopped lol.
 
#3 ·
So to be clear youve had to add 1quart of coolant in 40,000 miles? I realize you said you had to add a quart in the last 8k, but thats still only 1qt in 40k, so this could be normal coolant level drop due to evaporation, and seal seepage.

HOWEVER.....I have seen rare cases of failed cylinder heads leaking coolant into the spark plug bores, a small leak would be boiled off during operation and leave only dried residue in the plug tube if the leak is this small.

Secondly Iengines have been replaced for deck face/cylinder liner porosity. Apparently this is SUPER rare. but it was also presenting as cold start misfires, which you didnt mention

The first step in this situation needs to be a very accurate cooling system fill and bleed, to set coolant level and then monitor usage from there.

Again to be totally honest a complaint of 1qt of coolant "use/level drop in 40k miles would get shrugged off,(and rightfully so) by most shops. So be patient with your dealer/GM in rectifying any concern that may be present.
 
#4 ·
To be clear which I thought I was I have added 1 quart in 8000 miles. That means it went from full to a quart low in that time frame.

I'm looking for people with issues specific to the 3.6...not just generic problems it could be. I already know that lol.
 
#8 ·
So to be clear.... I DID IN FACT list two very specific issues relating to coolant consumption/loss in the LFX that I have experienced. Those being cylinder block porosity leaking coolant into the combustion chamber, and cylinder head concerns leaking coolant into the spark plug tubes.

:)
 
#6 ·
any wet coolant hoses/crack in the jug somehow? i know with the two cars i maintain it has seemed like the past two years i've been chasing coolant leaks on one or the other...i have a 3.5 not the 3.6 but through all the posts i've read on these forums i haven't seen any specifically related to an antifreeze issue on the 3.6.
 
#7 · (Edited)
No. Dry and free of dexcool slobber. The fact some made it in the oil means it's probably burning it which is my guess. I don't want to pull the plugs because I don't like working on this car but I will. Lol. Basically it's still under warranty and will be until next winter so I want GM to deal with it. Sometimes you have lead the horse to water lol.
 
#9 ·
in that case, you can keep taking it in to document the loss of fluid (hopefully you don't have a copay for each time they look at it). make them document where it is on the tank then bring it back when it's low again. i had to do that with the 2011 cruze about an oil leak. worked out in the end, just took some time to come to the end result where they fixed the issue.
 
#10 ·
Yeah I will keep at it with the dealership. They have record of everything and told me to bring it back if it continues to leak. Odd thing was they never topped the system off and just left it low lol. Like thanks guys haha. I know I won't mile the car out of warranty but it will time out. I haven't driven the thing now since the end of August haha.

It's never misfired or had any issues that way but I will be inspecting the plug bores and of course the plugs themselves when I pull them and take photos for recording purposes. If I find a cylinder with coolant present it will be going back to the dealership. Kind of torn though.. could just pull the heads myself and have my buddy redo them at his machine shop... at least they would be done correctly.
 
#12 ·
It's never misfired or had any issues that way but I will be inspecting the plug bores and of course the plugs themselves when I pull them and take photos for recording purposes. If I find a cylinder with coolant present it will be going back to the dealership. Kind of torn though.. could just pull the heads myself and have my buddy redo them at his machine shop... at least they would be done correctly.
Eff that noise....this thing aint an LS, no way in hell Id be popping off heads under warranty just for giggles. Youll get new ones from GM anyway if they porosity, spark plug tubes or cracking are the problem.

Youre talking 2-3 times more time to swap a head on the Impala than you would say an LS 5th gen camaro or pickup.
 
  • Like
Reactions: Carbide
#11 ·
nah, sounds like work and you have warranty for that lol. i've had great luck with the 3rd party warranty company route66. paid 2k for a 5 year/up to 100k on car bumper to bumper warranty for that cruze. it's paid for itself in the first year already. just a thought if GM can't figure it out before the timer expires on the warranty you have. wound up just re-financing for an extra 6 months through the credit union to pay for it. i'd do that again in a heart beat. we didn't add it until after the power train ran out from age.
 
#14 ·
No problems with our Impala like that but we just passed 20,000 miles on it.
 
#15 ·
Went to drive the POS this weekend and the dash lit up like a Christmas tree... power steering fail, abs fail, stability/traction control... sigh. Being under warranty I called the dealership and they can deal with it... then I think it can go down the road.
 
#16 ·
Our 2012 impala lt with the 3.6 has close to 140,000 miles on it, and to date(knock on wood) have had no issues with coolant loss/leakage or oil loss/leakage.

If it were mine and under warranty, I would demand the selling dealer find the leak and resolve it. No way I would be taking the heads off myself and voiding the warranty. jmho
 
#18 ·
Yea sounds like you got a bad one. You would get more money out of it if you got it fixed first though and got those warning lights to turn off. Good luck with whatever you get.
 
#19 · (Edited)
Lol...really. I was replying to the guy going on about the heads and I have said multiple times the car is covered by warranty so course obvious things will be fixed. It's booked in Wednesday and after that it can go. I probably won't replace it either as I never needed the car in the first place lol. If I do I will buy a new half ton or something.
 
#20 ·
You must have a bad dealer if you think they push the issue until the warranty runs out. The dealership gets paid by GM when the car is under warranty so they will fix the issue if they can figure it out. They don't do the work for free someone pays for it and when under warranty it's GM reimbursing the dealership
 
#21 ·
And GM also pays diddly in comparison to a book time job they charge the customer. If a job is let's say 8 hours book time GM might give them 6... If they are lucky. Now sometimes they can fluff it up with other things but the pay scale when it's a warranty job is not nearly the cash they make off charging you as joe blow. It's not a "bad dealer"... been to plenty of them. It's just the mindset GM as a company drives into them. My car passed a static pressure test... they did what was required by what GM said to do. End of story. I can keep taking it back and they even told me too if the issue persists.

However I don't really like the car anyway with how shitty on fuel it is... couple it with a bunch of issues... meh... I don't keep problems and complain about them.. I dump them and let them be someone else's problem.
 
#22 ·
can someone tell me how to bleed the system when you put new AF in? also other than draining the radiator is there anywhere else i should be draining it from
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top