Completely DISAPPOINTED in this vehicle. I bought the van used in 2003 from a respected GM dealer in Cobourg and of course I had no idea about the head gasket problems with these vans and they weren't going to tell me eh?. I have been wondering why I have been smelling coolant for the last couple years but could never find a leak. I checked my oil last week and I see sludgy cream coloured stuff, the tell tale sign of water mixing with oil. Of course that not all that's wrong with it. Two days after I bought it, the rear door handle broke but I thought "no biggie". Now the driver's window is screwed and you have to pull the window up with your hand while pushing the window button up. The passenger window is almost as bad too. The heater blower will sometimes stick to just blowing in between the windshield and floor, The stereo display was only half worked when I bought the van, the wipers "home" position is straight up, the rear door wiper doesn't even work. I haven't priced the head gasket job yet but I can just imagine. I have two months left to pay on this van and then I am DONE with any North American vehicles. I used to work in a place that made cooling system, hoses, and under body lines for GM, Chrysler and Ford. The company could never land a contract with Toyota or Honda..........why........? They're quality wasn't good enough! This tells you something doesn't it? The parts were good enough to sell to the "big 3" but not even close to sell to Japanese auto makers. It's this substandard quality that shows in these Montana vans and a host of other NA vehicles. Now that I've blown off some steam, I'll continue my new vehicle search. Looking for a nice HONDA. Screw you GM!

Symptoms: - Engine fault light coming on intermittently - Temp guage occasionally shooting up, then dropping back to normal - Sloshing sound from around the base of the windscreen (Air pocket in the coolant system) - Intermittent appearance of low coolant warning light.

Local GM dealer demonstrated serious incompetence by failing to diagnose the problem. They flushed the coolant system to eliminate the air pocket, without bothering to determine why the air pocket got there in the first place. They claimed that the engine light was coming on because someone forgot to replace the fuel tank cap before driving - total BS!

The following day - same problems occured again when driving on a highway - surrounded by fast-moving trucks and cars - only much worse: the engine overheated, lost power (almost causing an accident), the cylinder heads were damaged by the overheating. Returned to the dealership, really annoyed! They then informed us we would have to spend another CAN$2000 to dismantle the head of the engine to check for damage to the head gasket. When I explained my frustration about their failure to diagnose the problem, the service rep, then the service manager, explained that "there could be some corrosion or crack in the gasket causing the problem, but such a thing would be exceptional and unheard of for this vehicle". Clearly, judging from complaints on AutoBeef about 1999 Montanas with this problem, and the known problems with the manufacturer-supplied coolant causing severe corrosion, these guys are either totally incompetent or ready to spin the BS whenever it suits them! Their service manager made it clear that he could care less that their failure endangered my family! There was not the slightest shred of evidence of acceptance of any responsibility or offer of any concession.

Avoid the "Old Mill Pontiac/GM" dealer in the High Park area of Toronto (Ontario, Canada) like the plague. If they were the last mechanic / dealership on the planet, I wouldn't even recommend them to my worst enemy.

We asked around for a trusted mechanic, then took the Montana to a recommended local guy who, it turns out, used to work for GM. He understood the problem immediately and indicated that this is a well-known problem, and that he sees dozens of GM vehicles with exactly this problem - caused by the highly corrosive nature of the Manufacturer-installed coolant.

We had to pay for a head gasket replacement, all of the cylinder heads to be re-machined - CAN$2000. (Only $500 was the cost for the work recommended by the GM dealer at $2000). The coolant was completely flushed out and replaced by a standard coolant. This was an expense that could have been substantially less, if the GM dealer had done the job right!

The coup de gras: the GM dealer's used car salesman called me after checking their records and our complaints - to offer us the sale of a good used replacement Montana - at (I've checked typical resale values) about 50% above what they would normally cost.

It's a shame for GM. We called them. They exercise no control over the "franchise" dealerships. I like the GM products. I respect their award-winning manufacturing and safety records. The GM dealerships drive the GM customers away to other manufacturers.