Thread: Genral maintenance on my 98 GTP?

Ok, well with having problems on my GTP last night, I have begun to wonder more about a few things.

This car has 117k miles on it. Bought it off the original owner who took great care of her.

My questions are this,

Timing chain and gears. When is a good time to replace them? Do they have the plastic teeth on them like other GM cars? I know mine is original.

When should I worry about replacing the sensors, coil packs etc?

Since this is my daily driver, and has run fantastic for me for almost a year now, I havent worried much. Been wrenching on my 87 Cutlass more. But now that I am starting to have some problems, my GTP has become my centerpoint of maintenance.

Any guidance on it would be very helpful.

thanks

Craig

Originally Posted by hunter_alexander

Timing chain and gears. When is a good time to replace them? Do they have the plastic teeth on them like other GM cars? I know mine is original.

It's all metal. The only plastic piece is the timing chain damper which will eventually wear out, though I've never heard of one failing in a high mileage car.

Thanks guys. Thats what I needed to know.

Good to hear that the timing chains are all steel. The Olds 307 and other engines came with a timing chain that had plastic gears for the cam gear. This would always loose teeth, get into the oil pickup and ruin the engine. Thats why I figured I would ask.

I figured as much on the sensors, just curious.

As far as the regular maintenance, I have done all that already, fuel filter, tranny etc.

I was just curious as to the engine components and if there is a know fail point with them.

Appreciate the info.

Hell yeah. I am a member of various forums for my Cutlass and I find these places invaluable for help, research and overall data.

Been a member here since march, which isnt long, but I have gotten a lot of info from here.

The only recurring issue across the board for nearly all 3800 Series IIs is the intake manifold gaskets. They leak (mine were leaking by 45k miles).

I have read in the Catco catalog that also lists O2 sensors on the W-bodies it said replacement interval 80,000 miles.

There is a bit of maintenance that I would recommend at this mileage:

• Transmission fluid and filter - This is a big one in my book since the transmissions are one of the weakest points of the car. But if you take care of it and drive smart, it should last you awhile.
• Lower intake manifold gaskets - Probably the second biggest problem spot. Anything over 70k miles and these should be replaced. They just plain suck.
• Cooling system flush and coolant change - This fits right in when you do the LIM gaskets mentioned above.
• Supercharger fluid - This needs to be changed every 30k miles or so. Only when the coupler starts making noise should that be changed.
• Fuel Filter - Every 30k miles.
• Plugs & Wires - Depends on what kind you have. But should be changed on a regular interval. I would say every 30-50k miles or so.
• PCV Valve - Just cheap and easy to do every 30k or so.
• O2 sensor - Just the front needs changed every 50k or so.

As for timing chain or tensioner. I don't see a reason to tear it down that far to do. If it starts making noise from a wearing tensioner, then consider doing something. Until then, forget about it. Coil packs and other sensors only need changed when they are acting up, which isn't very often.

Again, this is just my opinion, so take it for what it's worth....which is not much

Thanks. That is a great list.

I thought that the sc 3800's didnt have that intake gasket problem. Thought it was only for the NA 38's.

for the O2 sensor, why only the front one? By that I mean, there are two right? Why would only the front one go bad?

Originally Posted by hunter_alexander

I thought that the sc 3800's didnt have that intake gasket problem. Thought it was only for the NA 38's.

Both engines use the same gasket design.

Originally Posted by hunter_alexander

for the O2 sensor, why only the front one? By that I mean, there are two right? Why would only the front one go bad?

The one in front of the cat has nothing to protect it in case of a overly rich condition or coolant burning in the combustion chamber or any of a number of things. These things can foul a O2 sensor pretty quickly.

The rear O2 sensor is sitting behind the cat (because its job is to monitor the cat's performance) so the cat takes care of a bunch of the nasty before it reaches the sensor.

Gotcha thanks.

Obviously I am still learning about these cars.