just Bought a 2002 montana what problems do they have?

[tysons]

I just bought a 2002 Montana ext. Was wondering what problems I should expect (common problems with them)?
2002 Montana Ext
199,000 Km
Full load exept power side doors,compass, on-star , power seats.
Is the intake/head gastket a problem in 2002?
Is the transmission any good?
Any info will be great.. thanks in advance tysons.

[dbudworth]

Funny you should ask. We purchased a 2002 Montana about a year and a half ago with 27k miles. Haven't had a problem with it till now (in fact, tonight), with 56k miles. I think it is the infamous intake and/or head gasket a problem. I've been doing some research on the internet and finding it to be a pretty common problem. It started out the the temp gage going up the the 260 mark, then acted like the t-stat kicked in, and then cooled down. When the temp gage started to go back down, then the heater would start to blow warm air again. Also had loss in coolant. All signs of this problem. Talked to a neighbor that is a mechanic, and he said the pontiac 3.4L V6 is know the bad intake valves and bad head gasket. I think this will be the last montana I ever buy again, since the only engine they put in them is the 3.4L. After reading all the problems people are having with them, I think I should get my fixed and trade it in.

[cdru]

Originally Posted by tysons

I just bought a 2002 Montana ext. Was wondering what problems I should expect (common problems with them)?
2002 Montana Ext
199,000 Km
Full load exept power side doors,compass, on-star , power seats.
Is the intake/head gastket a problem in 2002?
Is the transmission any good?
Any info will be great.. thanks in advance tysons.

IIRC, the gasket was redesigned last in 2002. So depending on when your vehicle was actually made, you may or may not have a intake gasket problem. Keep an eye on your oil and coolant. You don't have to it daily or weekly, but once a month just check. You should do that anyways.

The head gasket have been known to fail in the 3400 engine. However I can't really say if it's necessarily a common problem. What you have to consider is that the 3400 engine gets used very extensively in the GM lineup of vehicles. More vehicles running it will always result in more problems, but poportional to the total number of those engines, I can't really say if that is a problem. Just another thing to be aware of. It's not like you can do anything to prevent a problem.

The transmission is also not a very strong one. It will get you from point A to B, but the pressure control solenoid or 1-2 solenoid are troublesome due to a design flaw where they used a too soft metal that wears a grove.

Those are probably the biggest items that I'd keep my eye out on. Of course there are other things, but every vehicle has it's own little things.

[tysons]

Thank you for for the info, I will keep a close eye on the coolant/oil . My mech. thinks as long as I change the dexcool every two years that I will never have a problem with the intake or head gasket. He was saying that dexcool as crapy as it is crystalizes and becomes toxic. Destroying things like intake/head gaskets and rubber hoses.
I have never heard this about dexcool but will likely take his advice (can't hurt, I guess).
Has anyone heard about dex-cool becoming toxic?

[cdru]

I don't know about toxic, but it doesn't destroy gaskets. The problem was a enginerring design flaw, not a chemical problem. Many people who end up having intake or head problems also end up having Dex-cool issues with it chrystalizing (or whatever the correct term is) and they associate the two. Dex-cool isn't an issue if you keep the system well maintained and full of coolant.

[Glen_T]

I agree with cdru. From what I can tell from reading info on the internet and from looking at the technical service bulletins, Dex-Cool is not the reason for the intake manifold gasket issues.

From what I can tell, the original design was a carrier type gasket meaning it had a plastic "frame" with a molded in bead that actually did the sealing. The carrier made the gasket rigid and also lmited the amount of compression of the sealing bead. However, I believe the initial design did not have steel eyelets at the bolt hole locations called load limiters, but instead the plastic carrier limited the compression. Since it was plastic, not steel, you could only load it up so much.

The proper design (I think it is what the "fixed" gasket looks like but I don't know) has the steel eyelets. This way, you can put a fair bit of stretch in the bolts without overcompressing the gasket. More stretch is good since it allows you to continue to load the joint even after the bolts lose some of their preload. I think at one point GM even tried using longer bolts with spacers to get more stretch, and they recommend Loctite on the bolts to reduce load loss.

So, the real culprit seems to be a poorly designed gasket and joint, not the Dex-Cool.

Having said that, I'm not a big fan of extended life coolants. I've had direct experience with engine testing with the extended life coolants, and they are not all they're cracked up to be. They can attack the silicones in the gasket materials, so unless the engine was meticulously designed for use with the long-life coolants, you can have progressive erosion of the sealing materials. But GM knows this, and they would have chosen the correct polymer.

OAT coolants are just a way for people to be lazy and not maintain their vehicles as frequently, but that is my opinion.....Hope this helps....Glen