2003 Lesabre

I have a 2003 Lesabre Limited. When should I consider getting the timing belt changed? Is there anything else i should get replaced while they do the timing (other models sometimes recommend water pump, etc. since they are already in there ...). Any help appreciated.

Good news... You don't have a timing belt. You have a timing chain. Keep your oil changed and it will out last the rest of the engine.

On the water pump, you have a bell housing on the pump and it is easily replaced. You don't even have to remove the hoses to make the change. They basically take of THE belt take, unbolt the... well one other serpentine parasite and its done. The 199x's required raising the engine a bit, but not it is pretty easy. Just check for leaks and notice if the temp rises under load, and wiggle the power receiver on the pump to see if it is loose. Some replace it after six years. I replace all my hoses every six years because oxygen, heat, and other stuff is hard on them. You might replace it then.

If you have a few miles on the engine, I would get some electrical cleaning fluid, remove your MAF sensor (between the air filter and the engine on the air intake) and clean that little bitty wire you will see. It makes a huge difference in your gas mileage and rarily needs changing as must as cleaning.

Change you air filter every 25K miles if you are using regular filters. I like the reusable and just clean it out every 10K of so and put it back. I do that once a year.

Make sure to change your plugs at 100K. Use good ones from Bosch or other nicer brands. You don't have to pay $15 per plug, but good ones cost more than $2. I change them myself, though the rear ones are hard to get to. They have special tools to make it easier. The only reason i do it is to know what is in there.

I use Mobile 1 oil and do three filter changes and one oil change a year. I only use a quart in the whole year, minus the filter change topoffs. Again, everyone wants to use rock oil and synthetic is much better.

After 143,083 miles, I still get 30.2 mpg at 70 mph going through the appalachian mountains from NC to Pittsburgh, PA. I get 31.4 mpg @ 60 mph. That's off the computer and calculated.

Otherwise it is a very sensible low maintenance car that keeps on driving on the highway.

Now if I could get my lighter/aux power fixed.

Good news... You don't have a timing belt. You have a timing chain.
Make sure to change your plugs at 100K. Use good ones from Bosch or other nicer brands. Y.

I believe he was referring to the serpentine belt. If that is the case, the owners manual should tell you. The general recommendation is 60k or 4 years. That said, they last much, much longer. My 2000 had over 140k before I changed the belt. The old one was still in good shape, and I only changed it as my wife was going on a long trip. Look for cracks, etc. It is ok for there to be small cracks in the V groove side. If you are in doubt, change it. It is easy.

I would not recommend Bosch plugs. Buicks like AC plugs. There is a post on this site that goes into detail about not using Bosch, just can't find it..

I have a 2003 Lesabre Limited. When should I consider getting the timing belt changed? Is there anything else i should get replaced while they do the timing (other models sometimes recommend water pump, etc. since they are already in there ...). Any help appreciated.

Your water pump could outlast the motor. My 1998 has original at 168000.

I would recommend replacing the DexCool with fresh DexCool. The coolant, in my opinion, should be changed, replaced every 2 years or 36000 miles. I do not leave it in for 5 years and 150,000 miles.

Also I'd recommend using a drain and replace the filter in the automatic transmission every 36000 miles or so. I am not a believer in flushing especially where they don't drop the pan and replace the filter.

In addition, I used Dexron VI to replace the 7 quarts that gets drained out of the 12 quarts in the transmission. I used Supertech (Walmart) Dexron VI. You also can use Dexron III which is what the transmission shipped with.