Maintenance suggestions

My '98 Jeep Cherokee Sport 6cyl Auto trans has 160k with no engine or tranny repairs done. The radiator and water pump were replaced at

I love this thing and plan to keep it for 250k miles. My mileage has dropped from 20mpg to about 17ish and guess it's time to do a few things. What would you-all suggest for maintenance now at this high mileage?

Thanks,

Your distributor cap and rotor must be rotten by now....

Mike

Road Toad did pass the time by typing:

O2 sensor, before the excess fuel your passing out the exhaust kills the cat. And of course the usual air-filter.

timing chain should be checked... After you replace the distributor, rotor, plugs, wires, Coil, filters... check your timing chain for too much slop.

Actually Bill, most people who perform their own maintenance replace the oil, and a cheap K-Mart Fram filter too, every two thousand miles, because they like changing oil. They replace spark plugs at ten thousand miles or less, because the old ones look a little stained. The intervals quoted in the owner's manual are, as everyone knows, a little conservative and this guy deserves credit for pushing the envelope. It looks as if he is getting around 50k from transmission fluid, and 80k from spark plugs, and that is not bad.

Earle

"Road Toad" wrote in news:1140209103.619269.25240 @g43g2000cwa.googlegroups.com:

Milage drop is almost always O2 sensors. Check your air pressure too, 4lbs low can cost 1-2mpg. I run my at/ko's at 40.

"Earle Horton" wrote in news:43f6d92a$0$1101$ snipped-for-privacy@titian.nntpserver.com:

I do a yearly, or try to, plugs, cap, rotor, wires, skipped this last cycle and my milage is down a about 2-3mpg. Got the cap, wires, rotor on the shelf, still need to pickup the champion plugs. I've also run it from new at 5,000mi with mobil-1 bumper to bumper till I had the auburn put in the back end, thats got drydene now. I'm at ~290,000 or so on my 98XJ.

I'll check to see if I have the electronic ignition or not.......in any event it's time for the plug wires and O2 sensor at least. Plugs aren't due for another 20k but I may do the plugs while doing the wires.

Oil used is Pennzoil 20-50 w/Fram filter at about 7-10k

Tranny at 60k

Brakes last 60k

Have a great day!

Which interval do you use for the spark plugs? From my experience with the stock Champions, mileage begins to suffer after about 32k miles on a set of plugs. I realize that you can clean them and get more miles, but they are cheap and in my opinion not worth the trouble to reinstall used ones.

Your owner's manual calls for 10w30 oil. Unless you are racing this vehicle or submitting it to extremely heavy loads (you are not) then 20w50 will do nothing for you, but will rather decrease fuel economy.

If you want to use cheap paper element Fram filters, then fine. But they are designed to go along with the wasteful 3,000 mile oil change promoted by the oil companies. If you change the oil at 7-10k (many vehicle manufacturers now recommend 7k) then you are beginning to rely on the filter to trap particles. In that case you should use a good one.

The goal of responsible and economically sound vehicle maintenance is to get the most mileage while spending the least amount of money. In my opinion you will get more total miles from the vehicle, while spending some more money, not a lot. Where exactly you get the best return for investment, is a matter of some debate and individual requirements. You want to add into the equation, that it is less fun to drive a vehicle that is not performing as well as it could.

You have a great day too.

Earle