Regular maintenance schedule for a daily driver?

[Bilskirnir3124]

Hello all.

I'm new to this forum and to XJ Cherokees in general. A couple of family members have them, and after an, "adverse wildlife encounter," in my previous vehicle, I found a good deal on a 1997 XJ Cherokee Sport 4x4 manual with 205,000 miles. It's a 4.0L I6 with the AX15 transmission. The previous owner says that he had changed the fluids and oils not long before he decided to sell the Cherokee. I'm trying to figure out a good maintenance schedule for it. The intervals in the manual states some insanely wide intervals (7,500 miles for an oil change?!? No intervals for coolant and power steering?). I have an old chart I kept for my previous Honda Accord with these intervals on it:

Oil Change: 5,000 (miles)

Air Filter Change: 22,500

Brake/Clutch Fluid Change: 27,500

Transmission/Differential Oil Change: 45,000

Coolant Flush: 60,000

Power Steering Fluid Change: 75,000

Are these intervals good for an XJ? I understand that I'll want to change the Transfer Case oil even if I'm not using 4X4 often. Where would that slot in? What else should I add to the regular maintenance? Anything important I forgot to ask?

Thanks for the help.

 

[Ralph77]

While my '00 is the only vehicle I own I don't drive much.
And when I do it is short trips with frequent stops most of the time.
So much so that at least once a month I try to take the Jeep for a good run on the highway.
So all my maintenance is time and not mileage.
Oil change in April (10W 30) and October (5W 30) with conventional oil. Thinking 1500 to 2000 miles on the oil.
Napa brand to be more specific which is just rebranded Valvoline and a Napa Gold Filter which is just a rebranded Wix.
Air filter when needed cause I check it every April.
Brake fluid every April but I just suck out what is in the reservoir and replace.
Tranny fluid gets drained every other year in April in an even year. Cause there is a drain plug and for what 4 quarts of Dex cost screw it.
Transfer case gets done just like the tranny. Little tip when you do. Remove the fill plug first. LOL.
Coolant gets replaced in April every other year in an even year and I use the green stuff.
Only about 2 gallons comes out when you drop the lower hose so I figure there is always a gallon of older coolant in there.
Power steering every April but then again just suck out what is in the reservoir.
Gear oil gets sucked out every 5 years and replaced but I run synthetic Valvoline VV975 in there so...
Unless there is a problem spark plugs get swapped out every 5 years but I just use cheapo Champion 438's so....
Thinking the spark plugs have about 15K on them and they are only a 30K plug.
But the wasted spark thing makes me wonder so.....
Been doing all this for about 13 1/2 years now.

 

[Bilskirnir3124]

I drive just about the opposite of you. I live out in the boonies of Virginia, so no stop lights and 55mph speed limits for most of the distance of my drives except for when I cross town. I drive around 380 miles a week between work and recreation. Not hard miles, but lots of them. Thanks for the response. Taking not of the brands. I used to use Valvoline High Mileage Full Synthetic in my old Honda, and my Volvo 240 before it.

 

[Ralph77]

Well I mention some of the brands and types because part of that plays in how I do things.
For instance Napa sells an Extended Life coolant that could go farther.
But I like the green stuff.
If I used synthetic oil probably could change my oil once a year cause of how little I drive and it would not break down as much over time.
If I ran regular gear oil would probably do it a little more often.
Etc.
Because of the short trips with frequent stops my Jeep kinda falls in the severe duty category.
IIRC the FSM says 30K for regular driving and 15K for severe duty when it comes to the tranny fluid.

 

[Bilskirnir3124]

Well I mention some of the brands and types because part of that plays in how I do things.
For instance Napa sells an Extended Life coolant that could go farther.
But I like the green stuff.
If I used synthetic oil probably could change my oil once a year cause of how little I drive and it would not break down as much over time.
If I ran regular gear oil would probably do it a little more often.
Etc.
Because of the short trips with frequent stops my Jeep kinda falls in the severe duty category.
IIRC the FSM says 30K for regular driving and 15K for severe duty when it comes to the tranny fluid.

I had a little typo there. Should have said, "Taking note of the brands." Surprised the forum doesn't seem to have an edit button on posts.

Anyhow, I'm trying to figure out what's good for these vehicles. The engine is different from what I'm used to. All of my previous vehicles had OHC or DOCH engines. This one has OHV, flat tappets, and other tech that I'm not too familiar with. I'm trying to learn as much as I can so I can avoid any costly mistakes in the future.

 

[cruiser54]

30K on tune up parts, trans service and axle and transfer case service.

 

[Unclewolverine]

A lot of people swear by rotella diesel oil in your 4.0. I use it in my mail xj, (so extra severe duty,) and im up to 407k. I use a mobile 1 301a oil filter and change at 5k.

 

[Bilskirnir3124]

A lot of people swear by rotella diesel oil in your 4.0. I use it in my mail xj, (so extra severe duty,) and im up to 407k. I use a mobile 1 301a oil filter and change at 5k.

Do you use the 15-w40 or the 10-w30? I'm leaning towards the 10-w30 as I've always been leery of a weight of oil other than what the engine was designed for. Too much potential to starve the valves and crank shaft of oil or damage the pump. However I see a lot of talk out there about using the 15-w40.

 

[75SV1]

I have used Shell Rotella in my MJ and XJs since the 2000. I did switch to 5W-40 T6 a few years back. I did use 10W-30 T4 in the XJ. 10W-30 is speced for the 4.0L. I run synthetic for 1 year or at least 8K. It really depends on how clean your motor runs.
On the trans, I drain every year. Its about 4 quarts. I use a synthetic in the TC. Same with the diffs. The brake fluid, probably max is 5 years. Same with coolant. I use the Z05 coolant. Nothing wrong with the green stuff.

 

[Unclewolverine]

I use the 15w 40 most of the year, I use the 10w 30 for the dead of winter to quiet the valve clatter.

 

[75SV1]

I use the 15w 40 most of the year, I use the 10w 30 for the dead of winter to quiet the valve clatter.

I use the 10W-30 in my MB240D during winter months, before I switched to the T6. They have recently been making 10W-30 T6. I haven't tried it yet.

 

[Tim_MN]

Follow the service intervals and fluid recommendations specified in your Owners Manual or your Dealership Shop Service Manual. I use the severe service intervals.

Regular fluid changes are far more important than the brand name, the oil weight, or synthetic vs. regular oil. I use 10w-40 regular oil for summer, and 5w-30 synthetic for winter.

My 1998 XJ was a fleet maintained vehicle and received regular oil changes with whatever generic engine oil was in the 55 gallon drum. It has +290,000 miles and excellent oil pressure.

Some ZDDP is beneficial for the Jeep 4.0L, so I add a bottle of STP with each oil change.

 

[75SV1]

Rotella has around 1200 ppm of Zinc. That is good for the 4.0L and flat tappet cams. Some of the Break in oils are 1600 ppm.

 

[Bilskirnir3124]

Okay. So, it's looking like 30k miles is a big service. From what I've read through from your responses, it's a good time to do the diffs, transfer case, and transmission oils and a tune-up. Given how close 30k is to 27.5k I may as well check my brake and clutch fluids on the hydrometer for water contamination there as well. I doubt 2.5k is going to make much of a difference there.

As for the oil, I was doing a deep dive, and it looks like zinc, molly, and boron are only a part of the story, and that film strength is another very important part of it. Quaker State High Mileage Full Synthetic 5w-30 or 10w-30 appears to be a good contender with zinc content of 905ppm, phosphorous content of 751ppm, moly content 174, and a film strength of 125,083 psi at 230 degrees F. Much better film strength than Rotella T6 to my surprise. It also has gasket conditioners to avoid the gaskets shrinking and leaking. Something I'd like to avoid given that my XJ already has 205,000 miles. It's also got a great price on it. About $23 for five quarts or $6 for a single quart.

Did some deep digging on this blog post from an engineer. https://540ratblog.wordpress.com/

 

[Tim_MN]

The Jeep 4.0L is a 1960's engine design, any oil and some ZDDP will meet its' needs. Don't overthink it, just change oil every 4-6,000 with whatever oil is on sale.