Kahoona360

We bought a 2001 Keep Cherokee recently. It had about 130,000 on it. Aside from some 235 75 15 Nexen Radian AT tires and a new radiator it is stock. We plan to take it up Pikes peak as soon as they open the road to the top. We tend to go up steep slow rocky roads at high altitudes or in hot weather but we aren't aggressive. We plan to explore the parts of Death Valley that need a 4x4. What should I check or do to make sure I don't heat it up or otherwise damage it? We want to come back driving it. Does it need a trans cooler? Should I run a cooling system cleaner to make sure the flow is good? Obviously I will check and/or replace the fluids in everything. We carry boards, jack, tow strap and air pump.

ijeeep

I'd start with a good drain flush and refill of the cooling system and make sure the fan clutch is up to snuff. Then I'd add some redline water wetter for a small improvement in heat exchange. Hood vents help a lot in crawling and desert conditions.

Kahoona360

Can I do this myself with a cooling system cleaner from the store? If so is there one you recommend? I'll get the Water Wetter. Regular anti freeze?

ijeeep

Yes drain & flush is DIY. Every one has they're own take on cooling system cleaners or not. I've never used them on my rigs because I've never needed to.
A good trick is disconnect the heater hoses and hook a garden hose up to the heater core to flush it. Sediment tends to accumulate there because it's passages are smaller than the radiators and the flow through it is also lower.
Some of us go the extra mile and switch the garden hose several times between the heater core inlet and outlet to flush the core going in both directions to get out as much sediment as possible.

Besides keeping us toasty in winter our heaters are and additional way to help dissipate engine heat when needed.

BTW the heater control valves embrittle with age, crack and leak. All the replacement HCV's are utter crap with none lasting like the originals did. Almost everyone deletes them.

​​​​​​Don't forget to add a couple jugs of coolant to your "carry onboard" list. Thankfully my primary right seater/navigator/spotter/provider of delicious foods reminds me to so we don't get caught short...again.

Spencer_P

If the 0331 head hasn't been addressed I would before driving it in hot temperatures.
Also, inspect the radiator and coolant hoses and replace them if needed, along with the water pump and t-stat.

robsjeep

Death Valley in winter is cold, below freezing cold, snow. Death Valley in the Summer is hot, wicked hot, but it is a dry heat!

Replace old hoses, or carry spares. the lower hose out the pump oft lives the hardest life, but check them all



pick the correct gear when off roading, to keep the cooling fan turning enough. there is an electric modification to add a switch to lock the auto tranny in 1st when selector is in the 1/2 position, that can be helpful offroad. How if is the fan belt, idler pulley? Carry a spare belt, I even carry a spare idler pulley, had one go out in Death Valley! Before a long trip, make sure you have a fresh air filter, and that spark plugs are not wearing out bad.
A tranny cooler is always good if off roading, as that can heat up the tranny, same for hill climbing! I also added an inline tranny filter, Magnafine brand.

learn to air down your tires for off road! carry spares, tools, water, and warm sleeping bag if winter. it was in the low 20F at night last time I went in winter. in much of death valley there is no cell phone coverage! plan your trails, let people know your plan so if you're dont return, they have an idea where to search. Gas Stations can be few, have a gas can if you off road. If remote, have a firearm, and decent first aid kit, as you are far from assistance. a fire extinguisher is good to carry in the jeep, secure it so it cant fly around in a wreck.
The most important thing is .... Have fun!

awg

If it going to be hot, and you are off-roading, I would fit an auto trans temp gauge and larger cooler

after my AW4 failed, I installed a temp gauge, and was able to observe that climbing hills at low speed, (meaning torque convertor does not engage), at high ambient temps will cause the trans fluid temp to become excessive.

My previous AW4 failed under those conditions, if I had a gauge, I would have stopped if/when trans fluid reached 230F

It recently came close.

I already fitted a larger cooler, the PO had bypassed the stock unit cause it was cracked

Ralph77

I think half the battle is proper maintenance.
And keeping an eye on things between maintenance cycles.
I try every Monday to pop the hood and give the levels a once over.
Also just to see if anything bad jumps out at me.
Check my tire pressure.
I check all my lights too.
I go to my post office at least once a week to check my box.
They have this big window in front. I back up to it and check to see if my brake lights
and reverse lights are working in the reflection from the window. LOL.
Now I don't drive a lot and on top of that my Jeep is just a DD.
But cause of the way I drive, short trips and frequent stops, it actually falls more under the severe duty category.
Change my oil twice a year. April and October. Just use conventional oil with a Napa Gold filter.
Maybe 2500 miles on the oil when I change it.
I swap out my anti-freeze, use green by the way, every other year.
Just drop the lower hose, takes about 2 gallons mixed 50/50, and with my Lisle funnel get all the air burped out.
We have a drain plug in the tranny pan. Which is awesome. Every other year drop whatever fluid is in there.
Little less the 4 quarts comes out. Figure screw it. Do it. Now if we did not have that drain plug I would not be. LOL.
Same with the transfer case. Thinking a little over a quart for that.
Every April I suck out the fluid in my power steering and brake reservoirs and replace.
Small 12 oz container is more then enough.
Little over 5 years ago I swapped my diff fluid to an synthetic. Valvoline VV975.
Just last April I decided that I am going to swap that out every 5 years.
But I don't drop the cover. I just suck out what I can and replace it.
Sure it is overkill but I don't care.
Oil and filter probably run me about $20 each time.
A gallon green and a gallon of distilled water probably about $10.
5 or so quarts of Dex/Merc III is up there a bit. Probably about $20.
Thinking less then $4 for the small containers of power steering fluid and brake fluid.
Now the diff fluid swap can get pricey. Thinking that runs about $40 to $50 each time.
Having an '00 with the 0331 head I like to keep an eye on things.
Especially the coolant.
If it does crack would like to catch it fast. Before the anti-freeze has a chance to trash the lower end.
Better just a head job then a whole engine. LOL.

Kahoona360

Good advice about the flush. I will do that. I also want to replace hoses wherever there is any question. Preemptive is key.
I have been told that the auto trans is a weak point. Is that so on the 2001? If they remove the HCV how do they get heat? Water to drink and 50 50 mix for the engine. OK.I once had a 2 mile hike on the outer canyons of Death Valley turn into a six and I know about getting thirsty.

Kahoona360

Thanks!

Kahoona360

This 0331 head problem is making me nervous. Without starting another 0331 thread can you tell me how to find out if it has been changed and what it costs to have it done? No sign of any contamination of fluids showing.

Ralph77

First don't get all nervous. At least not yet.
You should educate yourself about it.
Also while you are researching things Google heat soak and misfires in '00's and '01 XJ's.

So basically the symptoms of a cracked head seem to be:
Unexplained loss of anti-freeze.
Milk shake looking oil.
Little or no oil pressure at an extremely hot idle.

Now loosing anti-freeze or low oil pressure does not automatically mean a problem.
Losing anti-freeze could just be a leak.
A low pressure reading in the cluster could be a not properly operating oil pressure sending unit.
Also the little port that the sensor screws into sometimes get clogged giving an wrong reading.
Always best to check with a mechanical gauge if something is suspect.

The head might have already been swapped cause of the problem.
Some guys use the TUPY 0331 head off later TJ's and WJ's.
They fixed the problem on those heads.
So pull the oil filler cap and look down in there.
See if you see the letters TUPY.
Look at the second picture at Post #2:

https://wranglertjforum.com/threads/...upy-head.8112/

Other guys buy the heads from Clearwater.
Best of my knowledge no way to identify one of those.

So depending on who you talk too:
Some guys say it is not a question of will it crack but when.
A mechanic at the Jeep dealership told me that they would crack somewhere between 75K and 125K.
Get past that point you should be good.
Gotta figure cooking the engine is not helping.
So IMO it is just basically a crapshoot.
I do get the feeling that this problem might be blown out of proportion a bit.

I own an '00 also.
Bought over 7 years ago kinda running and not really driveable. Got her cheaper.
Was aware of the head problem. Had about 147K on her at the time.
Now I know it is a regular 0331 head but whether it is original to the Jeep is unknown.
I am pretty sure I am the third owner. I have just shy of 170K on her now.
So far so good best I can tell.

Kahoona360

Welllll I looked inside under the filler cap and it does not say Tuppy. I will check the carfax in case it got replaced and noted. I did check the oil and coolant for traces of contamination. No gauges on our 01 Sport. I have 130,000 on it so perhaps I am out of the woods. I have only had it for a few days but it does not need oil or coolant. I do have the cylinder three misfire and am planning on replacing the plugs today. I'll see if the plug looks contaminated then. Looks like a head is a thousand installed give or take five hundred. I saw a lot of remans but I assume they are out of the question. Unless I get a symptom I guess I might as well do what I can to keep it cool and see what happens. Always something!

Ralph77

IMO that is one of the first things you should change.
For a DD ehh.
For what you plan on doing thinking more important.
My understanding it is plug and play.
It appears that any '97 to '01 cluster will work.
But I think '97 and '98 say the words "Check Engine" instead of the symbol that later models have.
Oh and there is the mileage reading to consider.
Appears stored in the cluster. So you either get one that is real close to your existing mileage or
pretty sure there are services to change it to what your mileage reads on the old cluster.

Ralph77

Oh something else to consider.
Might want to send an oil sample out for analysis.
Most people here use Blackstone Labs.

https://www.blackstone-labs.com/?ses...ct045%29%29%2F