4.0L mileage survival??
 

I bought my WJ at 188k, went through just about everything I could possibly think of to ensure it had a long and reliable life for me as my DD, and now as I quickly approach 270k it has developed quite the loud ticking on the top end and it got me wondering, just how much abuse and how long of life have you all really gotten out of a tride and true 4 liter??
I did a thorough engine flush when I first got her and have been running AmsOil ever since, but admittedly it has lost oil quicker than expected and I have run her quite low before catching it on occasion (usually noticed by a similar top end ticking that goes away once topping her off). :angel:

have you tried the 1qt of ATF for a few miles before an oil change? drain 1qt oil, ad 1qt ATF, drive around normal for 5-10 miles ... change oil. i've seen this work a few times on engines that were otherwise about to get pulled for rebuild.

how's your oil pressure?

i've had a few at 23x,xxx miles, only issues were caused from sitting. rusty rings and rusty oil pan.

I was going to buy Sea Foam before my oil change coming up in the next 200 miles, but I'll give that a whirl!
My oil pressure has always been great, just above the middle line! I cleaned out everything I could when I removed the oil pan to do the rear main 50k back or so, and like I said, have flushed the system several times throughout it's life with me. I really wanted to make it last to 300k from the get go (and knew that it was a teenage girl's first car, that lived on a farm, before I got it...). :pray:

Our XJ has 274,000ish miles on it. We have had it since 140k. I have done on BG epr (on a bet with the bg guy it wouldnt change the compression reading, I won) Maybe we just got a good one, but it doesnt make any lifter noise, still has 15-20 psi hot idle oil pressure. We change the oil every 5k (some times longer like when the oil pressure light comes on around turns :lol: ) wix filter, I run 15w40 rotella.

I have a 98 ZJ, 286000-ish miles. The engine runs perfectly, except for the AC, the pulley seized up on it. I bought used when I lived up in Iowas back in 2014. It had 172000 on it. Since then, I've had to replace an Idler pulley, alternator, water pump, fuel pump. I swapped out the front axles with CV joints, only because they were on sale and the u-joints were starting to squeal.
Other than the rust eating up everything underneath, and the common electrical gremlin, it runs great.

the cleaning agents in ATF are always more effective than i think, so the filter could be NASTY after running it. watch your oil pressure in case something comes loose and clogs the filter.

I had thought about that, may just do a filter change after he initial 1000 miles to be sure.
At this point, she drinks enough oil that I rarely change it, just do the filter every 5k and keep her topped off otherwise... :D

I routinely serviced a 98 XJ, starting around 250K, and the 4.0 finally gave up the ghost around 410K.

The owner had top end ticking starting around 320K along with low oil pressure (5-10psi hot idle). Switched out to 15W-40 from his usual 10W-30 and ran it until it lost all compression on #1 at 380K. He kept it going on all 5 until it windowed the block at 410K.

So yeah... heavier weight oil and send it.

I've had several in the mid 100s...highest I had was 225k til it threw a rod.

Current '98 XJ has 180k on it, daughter has driven it since 120s IIRC. Runs great, I've replaced a radiator, AC system, and brakes.

Had a TJ w/ 168k w/ a spun bearing, swapped in another w/ 125k and ran it another 10-15k before I sold it.

Always just changed oil w/ standard filter and oil it called for, never did any fancy tricks - about 5k miles, maybe 7k if it got long.

I regularly see XJs for sale w/ 200k on them, rusty, still selling for $3k to $10k :eek:

So I ran the ATF for about 20 mins (half bottle for first 10, second half for another 10) and then dumped the oil and filter and put in fresh oil and a cheap filter... the noise was just as bad.
I then added a bottle of Marvel Mystery Oil to run for that first 100-500 miles on the crappy filter... sound seems to have gotten worse.
Talking to Natey and Googling some stuff, seemed a lifter collapsed and I decided to park it until I can work on it to prevent unnecessary damage/unscheduled and immediate disassembly...
Yesterday I pulled the crappy filter (under 100 miles of driving on it) to put the fresh one on, before I pulled it into my garage for the time being, and the filter was EMPTY. Looked like I had installed it, let it sit, and pulled it back off 3 days later. I usually fill the filter once and let it seep in before install, but honestly don't remember if I did that this time, but looking into it you can see bare bottom!
HOW IN ZE HELL!?
For sheets and giggles I fired it up one more time, and it still builds oil pressure as usual, so how is this even possible!?
Any ideas from my original Jeep gurus?? :lol:

I'm heading to Vernal for WE Rock this weekend, but will tear it apart when I can cuz now I'm super curious. :confused:

if it aint going thru the filter ... it aint going thru the mains!

Is there a filter bypass on the 4.0? I thought some engines have a bypass for if the filter or a passage to it gets clogged :dunno:

no idea on the still-dry oil filter, that's kinda nuts.

Both of our 4.0Ls are still babies though. Just about to roll 108K on the XJ, and the TJ is under 96K.

I'll have to mess with it Thursday if I can find a hand, been out in Vernal for WE Rock all weekend. Ugh...

‘89 XJ was totaled at 40k, so who knows
‘89 YJ’s 4.2 stretched its timing chain at 189k
‘01 XJ went to 185k before needing a new head gasket.

Damn Dub!

Just rolled 108K as of yesterday. :lol:

Don't even have 39K on my 2016 JKUR yet, and it turns 8 yrs old in November. :lol:

:dunno:

The M-715 is 56 years old and barely has over 8k on it... at least until lately when it's my only running vehicle! :lol:

Dub - I have multiple vehicles as well, so you'd think I could keep some miles down - but holy damn. My JT is our main vehicle, so between going to CO, UT, weekly round trips to the cabin or visiting family all hours away, I have 44k on it already, and had 34k on the one that was totaled. Hell, I put almost 10k on my Vette back in the day and only had that ONE summer - guess I do like to drive :lol:

That said, my wife's Jeep has only 65k on it - 2014 :p

Lubes - that's a helluva daily driver :roflmao:
But, just knowing you - fitting ;)

Drive them like you stole them, I say :rock:

You should probably sell me the XJ. You know, to keep it limber and such. :lol: