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Oil - Tire Pressure

I have not been very good about oil changes on my 2002 Nissan Maxima with 118k. I want to do a complete change and feel that I should use some sort of cleaner prior to adding new oil and filter. I used to hear about using thinner or such into engine and run it before draining however doing this could cause problems with old seals, rings etc. Is there a product out there that is safe and recommended?

Also, Is SLIME, the tire product, any good as a prevent? My daughter’s tires seem to gradually lose pressure over a 2 week period and I thought something to prevent this would be useful.

Thanks in advance, G-Man

No to both.

Oil (and its additives) is its own cleaner. Drain, replace filter, and fill back up with the oil recommended in your owner’s manual. Repeat every 5000 miles or so and check the level every 500 miles or so and top off as needed.

Slime can freeze and cause your wheel/tire to become unbalanced. It is good in emergencies only. (I tried it myself for the same purpose you describe) However, if you live in Miami have at it.

" I have not been very good about oil changes on my 2002 Nissan Maxima with 118k. I want to do a complete change and feel that I should use some sort of cleaner prior to adding new oil and filter. "

More Information Is Needed. Answer these questions and you’ll get better recommendations:

Define "not very good about oil changes."
Approximately, how long ( miles) has it been since the last “complete” change ?
Approximately, how long has the typical change interval been or how many changes in 118k ?

Thanks,
CSA

I mostly agree with mleich.

Rather than additives, the OP should do a few cycles of frequent oil changes in order to clean out his engine. A neglected engine probably has begun to accumulate damaging sludge, and staying with a 5k interval is not likely to do much to clean out that sludge.

I would suggest changing the oil (& filter), driving about 2k miles, changing the oil & filter, and repeating that process one or two more times before reverting to a 5k schedule. Make sure that the car is taken out for a good high-speed drive for at least 45 minutes, at least once each week.

As to the tires that are losing pressure, the most likely explanations are either alloy wheels whose bead area needs to be cleaned & sealed, or tire valves that need to be replaced. The Dill company sold a huge number of defective made-in-China tire valves a few years ago, and it is possible that you have these poor-quality valves. In either case, a good tire shop can determine the cause and give you the proper solution, rather than putting Slime into the tires.

I agree with mleich, oil is it’s own cleaner. Unless you have any symptoms of sludging, just change the oil every 3-5,000 miles. The oil will clean out the remnants of lax oil changes without risking any damage.

Also, for slow leaks, a spray bottle of soapy water can find it. Many tire shops have a water trough they can dunk the tire in to find leaks, even very slow ones. Once the leak is found, it can be fixed correctly, and fairly cheap, even bead leaks. It will only get pricey if it is a sidewall leak that can’t be repaired, or a cracked rim, which MUST be replaced.

Sounds like good advice, Thanks. I will contact a tire retailer. G Man

Just change your oil. If you are worried about past neglect, do another oil change in about 3K miles. Then stick with a regular schedule, I like 5K miles.

It would be better to find out the real reason your daughter’s tires are losing air. Slime creates a real mess inside the tire and the next time that tire has to come off the rim you may be charged extra because the stuff is tough to clean off the inside of the wheel. A slow leak could be a nail, a leaking valve, or corrosion on the wheel’s bead allowing some air to escape. Skip the slime.