2002 Jeep Grand Cherokee Thermostat Replacement

We walk through the steps of replacing a leaky thermostat in a 2002 Jeep Grand Cherokee 4.7L V8. Hope it helps a little.
This is my first video ... sorry if it's choppy or blurry or inaudible in places.

[@laura-janebowser5361]

Thank You! Mechanic referral was going to charge $150 to change the thermostat. Dad changed it in 5 min with your guide. Already had the radiator drained and changed so it was an easy addition. Overall saved $400 with dad changing out!

[@kellykeck2517]

Thank you so very much for this video. you did a great job of showing the detail and explaining the process and technical side of this diagnosis and repair/ replacement. I'm quite sure you just help save me hundreds of dollars at the repair shop. THANK YOU, THANK YOU ,THANK YOU AGAIN.

[@troyviney7428]

My '02 Grand Cherokee overheated today...first trouble I've had with since buying it used with 198k miles on it six months ago. All signs say replace the T-stat first....Wanted to say thanks for this terrific video, I should be able to do this job in the morning. PS....my oil gauge reads at the same level yours showed.

[@stuartsabin4079]

On the 2003, there is a bleeder valve you have to open to get all the fluid out of the system. Its up top at the upper hose. Thanks for the video

[@tr3vorb438]

Very helpful! And thanks for the warning about getting coolant running down the armpit.

[@MotoRoUsa]

gread video I'm glad people have time to record their auto repairs sometimes. I'll replace my thermostat today and this video helps. Great jeep!

[@Traderhood]

Very much appreciate your effort to make the video and walk me through it!.

[@GmanWJ]

Vilo Conshmillo Glad you found it helpful. I have been doing lots of work to the WJ but no vids, hard enough just getting the job done, you know?

[@draggboy]

Just a little advice, if you find your T-stat housing leaking on this vehicle, replace the T-stat itself. There's no housing gasket, for one thing, so don't waste time looking for that. The T-stat itself has a gasket and that's what seals water at the housing. If you remove the T-stat and the gasket looks good and you're puzzled why it's leaking, just replace it. When you get the new one, you'll realize the gasket is MUCH thicker on newer T-stats. The factory ones were very thin and eventually leak. A new T-stat has a much thicker gasket (a rubber ring around the T-stat) and that's what does the job. Simple job. And REMEMBER, use only HOAT coolant in this vehicle. There are only 3 kinds. The pink stuff from Mopar, Zerex G05 (easiest to find without going to the dealership. O'Rielley's has it usually), and another one. Motorcraft Gold? Not positive. If one person reads this and I help save their radiator by warning them of using proper HOAT coolant, that's awesome. Some people will choose to risk it and use cheaper green stuff, but whatever you do, don't use orange (Dex Cool). It can turn to gel in unpressurized systems and either the green or orange is what caused me many problems including a new rad. Also, Dex Cool is OAT, not to be confused with HOAT which is only from Mopar and Zerex G05 (and the other one I'm forgetting). HOAT is usually pink or gold/yellow and more syrupy. Good luck, the cooling systems in the Jeep WJ will cause lots of headaches. Worst radiators I've ever seen. And one last side not, try to NEVER let your 4.7 V8 overheat much. Never risk it because they're very prone to warped heads, head gasket failure, valves dropping out, etc. The aluminum heads expand much faster than the block and at high heat they can easily warp and in many cases even expand enough to allow the valves to drop right out. Do your homework on JeepForum when doing any job on a WJ because they're very finicky, especially the V8 and especially the more exotic the options your model has. Lots of special fluids that DO matter and lots of other things like being picky about spark plugs, etc.

[@GmanWJ]

Aaron Dragg Good info, thanks Aaron. I would recommend using only Mopar coolant. My radiator developed a pinhole leak after this repair. Related? Can't say for sure. But now I have a new radiator.

[@dariom8045]

Thx U guys! I thought it could be the housing but now I'm pretty sure t-stat must be replaced.

[@CameronDC-Grimes]

Thank you man, this showed me how to drain just enough to replace thermostat in a 02 Jeep WJ (Laredo) I do have a few questions: 1. What kind of HOAT coolant did you use? I need the brand and # so I can buy it (what's the amount you put in) 2. Where did you get the Thermostat and what quality is it? My fan didn't turn on well past 250°F today. It's supposed to switch on after 220°f I believe. I turned off the Jeep instantly and let it cool. No coolant leak just had AC on while idling for 30min. ▪︎ The temp guage went to 260°F which is the end of the temp guage. After letting it cool for an hour and checking radiator fluid I turned her on and drove home 2 blocks. I'm wanting to make sure the thermostat works and the electric fan. I'll need coolant to check the thermostat and change it. I want a good quality thermostat so I don't have to worry about that failing and can diagnose the fan not switching on. Any tips? Id very much appreciate the info on HOAT coolant, amount of coolant and thermostat brand, website.

[@GmanWJ]

These guys can answer all your questions better than I. I use Mopar coolant from the Jeep dealer. Stant is a good thermostat. Your head gaskets are probably already leaking, do not let it get that hot. www.jeepforum.com/forums/wj-grand-cherokee-forum.310/

[@528freq8]

the amazing one-handed blind mechanic!

[@zerofuckkksgiven8027]

The skid plate is easy to remove! Also a 180 degree thermostat is a great upgrade!

[@JTTV72]

Awesome video. I have limited with 4.7L I was unsure on how to go about changing the thermostat. This video covered everything i was uneasy about. My Grand Cherokee would run about 210 then run hotter pulling up a hill with the AC on. She runs perfect now. Thanks for the great videos.

[@groovylilsexyhs]

Im haply I came across your comment. I have a 2003 cheeroke and my jeep says low coolant and started overheating, we changed the coolant and checked the fan and there's no leaks because we just replaced all the gaskets and the transpan, but its still over heating. So if u did then I can assume its my thermostat as well.......Did u have this happen too?

[@groovylilsexyhs]

Also I know this is a 6yr old comment, lol, but I figured u might remember 😁

[@groovylilsexyhs]

*happy

[@JTTV72]

@@groovylilsexyhs Hi I had a cracked thermostat housing and stumbled across this video searching KZbin. I would notice a small puddle of coolant in the driveway. My Grand Cherokee has a 4.7L V8 so not sure if you have the same engine. I found a new housing at my local NAPA store. I bought new gaskets and radiator hoses. This fixed my overheating issue. I previously had a new water pump installed I also put a new thermostat in it as well. I made sure I used Mopar coolant. I didn’t think it would matter but talking to a Jeep dealer mechanic they claim the Mopar coolant helps keep the water pump and other parts lubricated. I hope this helps.

[@groovylilsexyhs]

@@JTTV72 I have a v6 4.7L.... Thank you it helped a lot. I appreciate u running that by me and now I know I have to research for my exact engine.

[@TRUTH4U2NO]

Dex-cool and or red coolants will eat your gaskets and more. Always use green antifreeze/coolant.

[@konodennis7669]

This was a great video you made. Thanks this was very helpful, I bet I will save couple hundred dollars from the shop.

[@danielenriquepalomo]

thank you a lot, i replace my thermostat in my jeep grandcherokee 2007. basically is the same engine so have no problem in there. great

[@filmsbydiek7316]

Thank you very much!!! Handy vid brother!

[@fredirckoladapo8057]

Good recording and perfect fix

[@kellyshannon5785]

nice video but you need to know the bolt head size to inform your viewers of the correct tools to use ( 8MM ) NOT 9MM

[@centuryhousedw]

Good video, very helpful. Thanks!

[@twosnjuk]

Good job ... great video

[@dancook6322]

Thanks for your video!

[@bartlett1389]

my wife and i sold her car and got an 02 jeep just like yours and it has 157K and her oil press reads the same as that i thought it was just hers so i guess its a jeep thing in that year i like the vid it will help me when i go to have to do her t-stat

[@GmanWJ]

Mine has 159k now. Does require occasional maintenance, but it's worth it. Good luck with yours.

[@FLARE_NVME_509]

Hey thanks I got a engine light on and it's the thermostat on jeep commander 2006 hemi

[@slavn238]

Спасибо джипбро🤝

[@dolllady5804]

Great video.But I have never seen a thermostat located on the bottom side of an engine in the lower radiator hose.I'm changing mine tomorrow on a 99 Limited.Thanks

[@joshuacullett8644]

yeah im starting to think its the head gasket i might try some gasket leak stop and see if that works im hoping it might thanks though

[@rualmapa]

great job!!

[@petey1632]

I have the same vehicle, same year, model, and motor-- you mentioned how high the oil pressure is-- my Grand Cherokee had normal oil pressure for several years, then one day the pressure reading popped up as high as yours, and has stayed there since, always reading very high, even at hot idle. I think it's a gauge failing, and not accurate.

[@banditware]

Also why is your thermostat on the bottom. Mine is on top by valve cover. I have the same year as well. I've replaced mine before just needed a refresher and this just blew me away. I don't get your thermostat location here.

[@GmanWJ]

Do you have a 4.7L V8 like mine? 4.0L inline 6 may have a different thermostat location.

[@rvacarguy5480]

Hello I have a 2002 Jeep Grand Cherokee is well is the howling nosie normal I kept thinking it was the alternator but by listening to yours I feel like it's just the way the 4.7s sound

[@Musseinberlin]

So I had a similar issue with my 04 4.7 V8, leaking coolant from the same spot changed the water pump, fully flushed the system and I didn't change the thermostat. Now my engine never seems to go past 210 even with full AC blast. However when I open the hood I can feel heat rising up only in a single section of the engine right dead center between the alternator and the radiator. No where else do I feel hot areas only a small area in the front. Water pump seems fine no more leaks. I'm changing the tstat tomorrow and flushing the system again using the right coolant I read on these comments. Can anyone help? Why I have this rush of hot air? I don't think it's a hole anywhere.

[@jeanious2009]

What if the vehicle has green antifreeze istead of the orange dex-cool? The green coolant is 50/50 (distilled water) and it's been in the vehicle since I got it early this year.

[@jcstevegigs]

Damn, you skipped the hardest step!! I was just about to start this today, but my socket, (exactly like yours), won't sit flush on that top nut. I'm afraid I'll strip it! How'd you get it off? From the top? Thanks. Great video

[@GmanWJ]

Yeah, sorry about that but I couldn't reach the nut and hold the camera at the same time. I reached in from the top to get at it.

[@funtatentay669]

Great work

[@beaublahut]

There is a radio ad for Jeep Grand Cherokee in the background at 1:07

[@recorptnh]

Haha yea i heard that too. Maybe it was something like... "Take that grand Cherokee to the junk yard and get a chevy"

[@mrkeith1998]

+Jip Pers For what so It can get recalled.

[@neilbonard]

I loosened my pepcock but ended up snapping the grip part. Now I'm worried it's gonna leak

[@yeisonoscarninojaimes5852]

friend I have a concern with my truck, is a Grand Cherokee 2003 engine 4.7 she has Fan Clutch and an electric fan attached to the scuba, that electro must turn on the air conditioning or turn on to help the Fan Clutch? ... mine is disconnected and I would like to put it to work, thanks ...

[@dno440]

Great vid; question though, our 2000 Jeep Grand Cherokee V8 4.7 engine stays at the middle through town on a normal 60 degree day, and even driving on the free way up to 55 - 65 mph its a little higher but ok, once we get goin 70 mph it heats up to the line right before the red mark on the thermostat, now it is the all time 4wd mode but it is still really hot for normal driving conditions, do you think that would be a thermostat issue? or should I look else where?

[@GmanWJ]

It's possible. I've had thermostats fail on me like that on other vehicles. First check your coolant level. Recommend doing this first thing in the morning when everything is still cold, engine not running. Check both the overflow reservoir and the level inside the radiator (remove radiator cap). Also check level at the fill plug on the intake manifold. All should be full; if not, top off fluids with coolant mixture. If that's not it, the other two options are the thermostat and the water pump. Try running your cabin heater when the engine is hot. It should blow really hot air if your engine temp is red-lining. If it just blows kinda warm air, I would think hard about replacing the water pump. One thing for sure, you don't want to cook the engine that hot all the time. You could blow a head gasket and/or crack a head, and want to avoid that. I would replace both pump and thermostat to be safe. Hopefully that will fix your problem. It's also possible you have a partial blockage in the radiator. Myself, I let the radiator shop handle that one because it's a messy job and coolant gets everywhere. Good luck.

[@kroman72a]

Great video

[@jasonmonteiro7914]

i have minimal heat at times then the is coming out cold, does that mean my thermostat is going or is bad, or another big problem??

[@GmanWJ]

Jason Monteiro Could be. Cars are finicky like that. The problem could be anywhere in the cabin heating system. The thermostat is one of those parts. However, if you don't have overheating problems, then it's unlikely that the thermostat is causing your problems in the cabin heating. My take is that it's more likely the electronic climate control panel on the console. I had to replace mine because the AC wasn't working properly (that ticked me off for a long time). Sorry the response took so long; I'm not here that much.

[@MrSexy4durant]

My jeep is running hot when its sitting for a long time. but when i start going the temperature hand goes back to normal. Is that a sign that i need to replace my thermostat?

[@draggboy]

It definitely could be. No leaks that could cause it to lose pressure and prevent it from circulating enough at idle? It could also be a clogged or restricted heater core and another very common one in these vehicles is worn water pump. You can check all your hoses, make sure there's no leaks flush the whole system really well as well as back flushing the heater core (separately so no gunk gets in the actually cooling system - look up Eric The Car Guy's tutorial which is actually on a Jeep WJ), replace thermostat and refill with proper HOAT coolant from the dealership (Mopar) or Zerex G05 from O'Reiley's. If you still have a problem and there's no sign of leaks, it's very likely the water pump.

[@MrSexy4durant]

turns out to be a relay switch.

[@mikekool2829]

Kendrick Golden so u replaced relay switch and your jeep stop running hot at idle, mine does the same thing

[@topher037]

Kendrick Golden mine is doing the same exact thing. What relay switch did you change?

[@sdog325]

So I just replaced the tstat and stillover heats I also hear a noise when driving like from the pulleys possible water pump ?

[@GmanWJ]

Jss05 Several possibilities really. Low fluid, radiator blockage, faulty radiator cap, water pump, head gasket, or yes even a bad thermostat, it happens even with new ones. You could test the tstat by driving without one (not strictly required equipment), if still overheats it's not the tstat. Pump would be the next thing on my list.

[@sdog325]

Working Stiff appreciate it but it turned out to be an air bubble in the system

[@GmanWJ]

Jss05 It could also be that the system is not completely full of coolant! ;-)

[@joshuacullett8644]

i have an 02 jeep grand cherokee and have changed the thermostat the radiator and the water pump and its still overheating

[@GmanWJ]

Joshua Cullett Sounds like a blockage. Do a system flush, replace all hoses, another new thermostat, and get the coolant ratio correct. I would take it to a shop for the flush. If none of that works, I would suspect head gaskets.

[@elisabethharris423]

What size bolt is needed that holds the housing of the thermostat 2000 v8 jeep grand Cherokee. mine is stripped and cant get it off.

[@GmanWJ]

+Elisabeth Harris It's an 8mm bolt. See text note on the vid at 3:02.

[@fernandoguerrero9498]

Does it need any sort of gasket?

[@GmanWJ]

Fernando Guerrero The gasket is built in to the replacement thermostat.

[@jaymo3454]

what size is the socket to remove the 2 bolts?

[@GmanWJ]

8 mm, see 3:06

[@johnhumphrys3815]

8 mm socet for the two bolts . carfull not to breack off bolt if seased up tight may want to use heat flam on housing just before un tighten tight stuck bolt .wouldnot want one to break off

[@jcstevegigs]

@@johnhumphrys3815 This is why my mechanic didn’t replace my T-Stat when he flushed my Radiator. Now radiator is leaking and I might try to replace the rad and tstat. What if bolts break?!?? If I apply torch won’t it melt black plastic housing? Eventually those bolts will need to come out. Are they prone to breaking? What about spraying with WD40 or PB Blaster? Thanks for your input!

[@jat-justamaturetech-philpj8285]

No housing gasket???

[@GmanWJ]

Rubber gasket was built into my thermostat.

[@FLARE_NVME_509]

Hey thanks I got a bad sensor

[@johnaranjo6354]

No gaskets?

[@GmanWJ]

john aranjo Gasket is built in to the new thermostat

[@edwardmurrow2368]

is the country music optional?

[@GmanWJ]

+Edward Murrow No, in fact I recommend a constant stream of Taylor Swift during all your repairs.

[@edwardmurrow2368]

Working Stiff ok thanks, I actually tried this with wiz khalifa in the background and my entire cooling system exploded... so lesson learned I guess.

[@joecartwright3674]

Why are you draining the rad..??

[@GmanWJ]

+joe cartwright If you don't drain the radiator, the fluid will all come out when you disconnect the lower radiator hose.

[@RedFTW89]

I hope that's where my leak is coming from. Much easier than doing a water pump.

[@banditware]

Water pump. It's coming from the seep hole in the water pump. That's what's it for 😉

[@jesusmariavaldes1289]

No se vio cuando quito el tornillo de arriba

[@regrob16]

does anyone know where the coolant temp sensor on the same type of truck?

[@mrkeith1998]

+Reginald Roberts Kinda late but may help someone else. It sits In the middle below the Intake manifold,. not on the manifold below It. The MAP sensor Is In the middle of the Intake, so don't get them confused.

[@regrob16]

4.7 V8 HighOutput Thanks a lot. I did find it. I didn't expect it to be in that location. Thanks again

[@adamJeepstuff]

Lol thx, my coolant have been leaking very slowly

[@FLARE_NVME_509]

Perty similar

[@ktdgolive405]

WJ use gold HOAT COOLANT

[@GmanWJ]

Fact: WJ use Mopar MS-9769 orange coolant

[@ktdgolive405]

@@GmanWJ I swore the manual said specifically gold HOAT. Maybe I'm wrong but I've read multiple forums that specifically name zerex g05

[@GmanWJ]

@@ktdgolive405 If you drain and flush with distilled water you can swap to zerex HOAT, but do not mix it with your orange Mopar factory-supplied coolant.

[@johnmorell2663]

Why wouldn't you take off the house.