I just replaced the lower intake manifold gaskets on a '99 Olds 88 after noticing what appeared to be a coolant leak. The upper was done at a service shop about a year and a half ago, but they did not do the lower. The car only has 48,500 miles on it, and is not driven hard, as it is owned by a 90 year old woman. She doesn't drive like your typical "old lady", however. (Not exactly the "Little Old Lady from Pasedena" as mentioned in Jan and Deans song, but she holds her own with traffic.) She has regular maintenance performed, and had the DexCool flushed out after 3 years. I was surpised at how bad the gaskets looked.

http://pg.photos.yahoo.com/ph/archon...36.jpg&.src=ph

http://pg.photos.yahoo.com/ph/archon...24.jpg&.src=ph

The heads and LIM showed some signs of pitting, also. (Sorry, no pics of that as I didn't have my camera with me.) There has been some discussion on when to expect the lowers to go, so I thought some may be interested in seeing these at this "low" of mileage.

The one thing regarding her driving that is likely a factor is that a lot of short trips are made with the car. She lives in Detroit, and often just drives to a nearby coffee shop, to church, and to the store. Her last car (I think it was a 96 eighty-eight) spun a bearing after the gaskets were replaced. This could have been a dealer service problem, as GM ended paying all but $50 to have a short block put in.

It would seem that how the car is driven during the miles that are put on is at least as important as to how many miles are on the odometer.

Those pictures don't surprise me one bit. The lower intake gaskets on my 99 looked the exact same way after only 77,000 miles. The good news is, at that time I replaced those gaskets with Felpros. At 115,000 miles I pulled the lower again and the Felpros still looked like brand new. Of course, I changed them anyway.

Did you happen to change the coolant by-pass elbow? And, what brand of gasket did you go with?

Yes, I did replace the coolant elbow also. I used Felpros for the upper, and the new GM gasket for the lower. The place where I get my parts even called his Felpro distributor to see if perhaps they had one-upped GM on the lowers. They had not....at least yet.

As a side note, I was not impressed with the way the upper had been done previously. I know they're only 89 in lbs for torque, but I could easily get them out with a nut driver, and no indication of any thread lock being used.

When Bill Buttermore and I did my replacement job in March the UIM bolts broke loose way too easily - was a bit disconcerning - but I wasn't losing any coolant at the time. Not sure whats up with that though.

I would have felt a bit more comfortable if they had "broke loose". Unfortunately, they just spun out. Luckily, it hadn't appeared to have caused much of a problem.

89 inch pounds really isn't a lot of torque. You can probably apply more torque than that with a screwdriver. So i'm not supprised they felt loose.