I work in a local automotive shop in town changing oil and rotating tires. Kinda working my way up if you want to call it that. Well yesterday one of the other guys I work with suggested I start using Mobil 1 with Lucas in my Jeep. I have my own concerns about it ----

1. My Jeep is about roll over 175K soon.
2. 03 model, nothing wrong with the motor. Starts and runs fine. No leaks other than valve covers which can be fixed easily.

My question would be, is it a safe and wise investment to switch to Mobil 1 and adding Lucas, or do I stick with the oil I've been using all these years which is Castrol GTX ?

 

Safe? sure it's safe. Maybe a little oil leakage, maybe not. Wise? Probably not. I am VERY leery of any additives. If the oil has a good additive package it shouldn't need any additional additives. You got this far with your current oil I would stick with it. I feel that regular oil changes are more important than running synthetic or regular oil. Just my .02 worth

 

That's kind of what I was thinking. I've ran Castrol since I've had it.. the recommended weight of course, and I've never run anything else and never had problems with it..

 

I've always had the opinion of only using oil additives if you think there's a reason to, i.e. pinging, possible stuck lifters, etc. And I think they should only be used towards the end of your oil cycle because if you happen to knock some crap loose in your engine you're going to want to drain that out sooner than later. If you already have leaking valve covers synthetic may make it worse just because it's thinner oil, but apart from that running synthetic in your Jeep wont harm it. It also comes down to how much you want to spend. Mobil 1 isn't the most expensive, but it's sure a bit more money then the GTX. I run the Mobil 1 Extended Life in my GC because I like going longer between oil changes as it's not always convenient for me to do every 3,000 miles.

 

Leaking valve covers, especially on a V8, suggests plugged oil drains in the heads. When this happens, oil collects higher in the heads above the gasket surfaces and leaks out. When you redo the gaskets, check your drains. This is especially true of Chevy small blocks because the drains are only small drilled holes in the lower corners. IDK about the Mopar motors.

On the choice of oil. I would run whatever you normally use. With regular changes, additives aren't needed.

 

Good points here. In my younger years i ran Castrol and it worked great. I have run all kinds of oil and even the generic stuff when I had to but always changed oil at 3000 whenever possible. Today I run Wolf's Head Oil with Lucas when I can because everything I have now is high mileage. Meaning 170,000, 205,000 and 260,000.
I think the important thing here is to change oil on a consistent schedule with a new filter. I buy cheap oil filters.

Here is one for you. I had a person tell me once to ATF to my oil to help clean up the engine. They also used ATF in the gas tank to keep injectors clean. Any thoughts on that?

 

You can use ATF in your oil but it should be added right before an oil change. Basically add a quart of ATF, idle for about 20 to 30 minutes, then do your oil change. I never heard of using it in your gas, but from what I've read Marvel Mystery Oil is basically ATF and you can use it in your gas so I'd imagine it wouldn't hurt. I'd use small amounts like you would MMO though and don't go over board with it. IMO I really like MMO. I use it for a general purpose lubrication not just for my cars but for things around the house as well. It's cheap and it lasts long. The one thing I can't skimp on is a decent oil filter. I usually use Bouch because it's a good filter and not over priced. I can pick one up at wally world for about 6 bucks. I stay far away from orange filters with bed liner sprayed on them.

 

ATF is basically a high temperature, high detergent hydraulic oil. It has incredible lubricity for it's low viscosity. I can see why it would break down sludge quickly. You can even use it in place of WD40 to break down rust, although it takes longer.

Another piece of stupid trivia. Did you know at one time J C Whitneys sold an oil filter that used a roll of toilet paper as a filter media? How dumb is that?

 

Additives dont fix long term problems but I have seen the lucas stuff quiet down some noises and improve some oil pressure concerns but its not a mysterious problem solver. Synthetic oils are good for certain purposes or engines but I dont think you would necessarily benefit from using one unless you wanted to extend your oil change interval.

Oil filters are important too. Since you do a lot of oil changes here is something you can do out of curiosity and boredom. Start collecting different brands of oil filters and cut the can open to inspect whats inside. I use a cut off wheel and cut around the filter can just above the crimp on the threaded end cap. Depending on what brand your shop uses or yourself you might find another benefit to oil changes by switching filters.

I found most major brand name filters including the OEM's are decent (except fram) and most of the cheaper "house" brands used by lube stores, auto parts stores etc are not very good either. Cardboard end caps on the filter media, cheap bypass springs, and less filter media are some of things I've noticed in some brands.

 

Cutting open an oil filter on the first oil change after a rebuild is standard practice for race engines. You can rinse the paper through a piece of white cotton and see if you have strange metal particles in it, things that will tell you if you screwed up the assembly. A few fine aluminum bits are normal from installing the pistons, but should be gone on the second oil change. We only ran the engine about 1 hour before changing the oil the first time.

My personal preference is AC.