Hummer H3 Radiator Replacement COMPLETE GUIDE

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Complete guide on how to replace the radiator in your Hummer H3.
Disclosure: This site contains affiliate links for which I may be compensated. As an eBay Partner and Amazon Associate, I may be compensated if you make a purchase through these links.
Buy radiator for way less than auto parts stores here: ebay.to/2vklknI
Radiator cap (HIGHLY recommend replacing this): ebay.to/2wjceMw

[@titan_husker]

WOW, even for a disabled guy, this repair was doable. On the 2007 model, there is literally only one bolt that holds everything together. This hummer has never had heat as it does now. Very happy wife, even happier come this winter. Thanks again.

[@roadtrippinwithdea7261]

Thank you!!!! I took my iPad out in the garage with me and went along with you step by step and got it done!! I never could have done It without you! I have never done any mechanical work before! ! 😊😊

[@regisshea554]

AWESOME!!

[@dognatious6153]

awesome. im going to diy too.

[@JustContinuous]

This video is awesome. Your step by step was very easy to follow and just works. The shops wanted to charge me over $1000 for radiator replacement. I did all the work and spent $170.

[@bethanydavenport843]

You there? Tryna find a radiator that’ll work but won’t be to much.

[@marvind1549]

For those of us not so mechanically inclined, thank you so much for walking through the radiator replacement step by step.

[@instanttang1771]

Great video! These plastic tank radiators seem to last only 75k miles for me and this video saved me at least $700.

[@travelbucketlist8968]

What a great video. Thank you. The dealer wanted $1,000 to replace my radiator.

[@ricaldrich3424]

UPDATE: I followed your directions to the letter...Except for putting it on ramps to bleed the air out of the front of the motor. (I didn't have ramps) The motor was running hotter than usual on the Freeway and at lights. I bought a set of ramps did what you said BOOM temp is perfect actually running even with the middle mark it used to run just on top of it. Usint the vicegrips on the clamps was a lifesaver.

[@InCountry6970]

Great video. All these years with my 07 H3 and I never realized the fan shroud came out that way. Thanks

[@charosenz]

WOW. Super job on Vid. Now I feel ready to tackle this. Thanks for not adding annoying music so many other guys do.

[@ggeneh71]

Great video! It's good to see someone that knows what they're doing. Thank you for posting

[@1jandsjensen]

My son and I were able to complete this task in his 2007 H3 because of this video. Thank you!

[@robh2907]

The best instructional video on this subject. Saved me $300 today and finished in under 90min. Awsome thanks

[@robh2907]

Sorry, so happy I posted twice...lol

[@robh2907]

Saved me over $200 in mechanic fees!! Great detailed step by step video.

[@donmatthews5231]

Thank you for taking the time to upload this video, I am not taking this to the dealership I can handle this with the help of your video.

[@Snailmailtrucker]

They are called *STEALERSHIPS* not Dealerships ! *LET'S GO BRANDON !*

[@sharabi21]

Really done well. Clear, concise to the point with excellent video clarity. Thank you and keep up the good work 👍

[@rdcopley1]

Good stuff. Covered A-Z. Got me through a job I have never done before. Used the rad and cap from the link, I didn't have to scavenge parts from the old rad. Thanks again

[@oberthus1]

honestly didn't even know my fan shroud did that. you will save me a lot of hassel in the future. Cheers.

[@johnsonner4168]

Great video. All the details needed including the socket sizes. Walked me right through it.

[@paparenegade7322]

Thanks for the info, the trans line is what I wasn't sure about,,, great vid

[@behoward425]

Very good and thorough video. Super helpful. Thanks!

[@mikemartin168]

Thank you man, just knocked this out today with the help of this video

[@MrCrf450rider]

Good video! I have to replace mine too.now I know what I'm in for,without any surprises.thanks!

[@donp2474]

Great job! Clear, concise instructions and video

[@702cadi]

Good job. I was a aircraft mechanic for years u know your stuff

[@fixerone1963]

Great step by step video. This will make my job easier.

[@joshuabradley1057]

Thank you for this video. It was a big help.

[@kunyaization]

Thank you for the video, from KAZAKHSTAN 👍

[@DanielLee89501]

Watching this gave me the confidence to tackle this job. Like everything, it took me a lot longer than the video to do the exchange. My new radiator didn’t come with new nuts for the side connections, so I had to recycle them from the old unit. The tip on using a pick tool was essential to disconnect the transmission cooler lines. I replaced the radiator cap and nearly one quart of ATF fluid (Type VI) also. Be prepared. Thank you!

[@papo-rc9173]

Thanks you help me a lot. Great video.

[@pmakris3552]

Hi great video. Very detailed from start to finish.

[@masterroshi23]

Thanks so much mate.. You really helped me out today

[@zrig1]

Should mention that GM's require Dex-Cool or "Universal " coolant. Use regular Prestone you will cause problems with leaks in the aluminum components in your engine and cooling system. The jug you used did indicate Universal but could be easily missed.

[@livinglife4921]

Thank u for video man having to change mine on a 2007 h3

[@romanroman1975]

Awesome, thank you for the video!

[@liamkneeson8866]

Awesome video, thanks for sharing

[@angelasuncion8395]

you don’t need to remove that clips for transmission line in the new radiator all you just gonna do is push the lines in and it will snap in to places

[@dognatious6153]

Oh, thanks Angel for clarifying that. The video above was unclear about that and I was scratching my head because another video implies what you just said. So you are correct. But to remove the old radiator and the lines you do have to remove the clips just like Angel says, people.

[@DLR-gz6tv]

Awesome video. Thanks for posting!

[@itachi7415]

Thanks for the video, helped a lot.

[@f296877]

Awesome video! Thanks 👍

[@spydernetwork2289]

When trying to get the AC condenser coil into the lower slots I was putting what I thought was light pressure on the coil and dented the top of it where my thumb was. Will this cause an issue? Should I have tried to lift it back up carefully? Everything else went smoothly but hoping I did not cause a future issue and was wondering if I should be looking for something. Thanks

[@elpalenquedeoro]

Great detailed video

[@TheHummerChannel1]

Hey man great video. My radiator just gave out on my 06 with 177,000 miles. I'll be doing this next week. Mine has some foam at the top to protect the top of the radiator from rubbing against metal. Did you find yours rubbed on metal? Thanks!

[@nasuper100]

great Video , but what is with the Transmission fluid refill ?

[@hassanjassoma5809]

It was very good instructions

[@oclaothug69]

Awesome video 👍

[@CanadaLifeVlogs]

Great video

[@khstorage4528]

Nice job! Thank you ma'am!

[@jaimeBP]

este video a sido de mucha ayuda ya que tengo que sacar el radiador de una hummer h3 de mi papa mañana jajaja excelente video ideal hubiera sido en español

[@emmanicholls1069]

My question is, would the rad be a possible cause for leaking? I know I have a coolant leak I just have to get it to the shop to see where it’s leaking from. Most likely an old line as my hummer is used but I got home today and my rad was smoking a bit. So I feel that this is another issue I have to fix but would I need to replace the rad if my coolant is leaking? It looks like it’s leaking right out of the rad somewhere and dripping to the pan and off the little pan lip on the driver side. Thanks

[@dognatious6153]

excellent video! excellent!!!!!

[@davidgreen8089]

DONE !!!!! 10 of 10

[@ruana509]

Hi there I replace the radiator on my 2007 hummer h3 thanks for the video only had one problem went I added the transmission fluid I ad it one quart and I think I over did it so today I pump it out. I'm having trouble checking the oil level is a little tricky to get the exact measurement. My question is how many onces of transmission fluid did you ad after replacing the radiator?

[@juanvazquez8531]

Ivan N the to

[@CompTechMike]

Is that fan shroud aftermarket? I have an '07 Colorado and it uses a two-piece shroud. I do see some one-piece shrouds on Amazon, however? Also, is the metal skid plate aftermarket or stock on the H3?

[@damianromo7051]

I'm (older) female & this would be my 1st DIY auto work/replacement. I'm gonna replace the water pump & radiator, for ease of removal & installation. Which one should I remove & install 1st. & 2nd? Please help & TIA

[@JOSERAMIREZ-og1jt]

Thanks very helpful 👍

[@willosinger8462]

Well done 👍👍

[@maddog5814]

What's that on top of your skid plate? I am curious to see how all the various seals and buffers are located to re-direct airflow. Removing some of those could make your truck run hotter. Would be cool to see a video on that.

[@ThePelicanDesigns]

This guide helped.. but I ran into a frozen coolant line (remove the entire fitting from the radiator if needed), and my condenser was attached to my stock radiator with 3 plastic fittings. So the part when you show the radiator and condenser separate easily the left side stayed attached and I fought with it until I noticed the 3 fittings and cut them.

[@ZzzanetaNorv]

hi which hummer engine is more reliable, old 3.5 or newer 3.7. Thank you.

[@krazmex09]

Went to the beach the other day, drove on sand and out the blue i got this plastic smell. And notice the temperature went higher than usually. I parked and checked what was it, never found out and when i turned h3 back on temperature was normal less plastic smell. Could this be radiator? I checked cant seem to see no leaking or water dropping neither

[@elbucio4462]

Thankful for this video! I was going to get charged 1,000.00!

[@davidgreen8089]

THANK YOU

[@ricaldrich3424]

Thanks for a great video $950 to have my mechanic do it

[@dragonl300]

**I just change my 2006 H3 radiator., set the heater on high- hot,.. but didnt blow any air inside at all, and the AC line "froze"... whats wrong , is that a sign that it need any 134a feon?**

[@phantom_stream]

I seen that you used the green Coolant instead of the red. Does that make a difference? Also how much do I need to refill? Thanks

[@regisshea554]

Never do that..... Ethylene glycol does not mix with Dexcool and Hummer H3's all use Dexcool! Engine block still had orange Dexcool in it.

[@JakefromSF_NM]

Ya never use any other coolant in a Hummer only Dexcool

[@hassanjassoma5809]

Excellent

[@darrenw.taylor2084]

I noticed at the beginning of this video you said that was a 2006 H3. Would this pertain to all H3's with the 3.7? I have a 2009 and it looks the same.

[@regisshea554]

Yes, exactly the same radiator....

[@brendacassata9885]

What size radiator does a 2007 Hummer H3?

[@regisshea554]

@@brendacassata9885 All Hummers take the same radiator. All years, and all motors. Even the 5.3 v8 uses the same radiator.

[@conradovargas71]

Hey do u need to add transmission fluid when replacing the radiator???

[@RotaryCrossType7]

YES YOU DO! Your going to loose a liter or 1.5l so if you don't........ well you know what happens....

[@patmiller2415]

Me too, this is the 1st time I did it by myself (old lady, kind of hard because I don't have muscle). Do I have to remove the spring clip or leave it in there? I removed it, then inserted the trans line & I had a problem inserting the spring clip back. I don't know if it inserts properly or not but I'm guessing it's not sitting properly because the plastic rings do not sit flush with the opening. Please (anyone) let me know ASAP so I can finish the job. Another problem is I got a lot of trans fluid coming out (maybe 2 qt.) so I need to fill the new trans fluid back in.

[@AutoRex101]

It is easier to re-install the spring clips prior to installing the lines. The clips are designed to expand when the lines are inserted, then engage with the notches on the lines to hold them in. You should hear a little click when they engage.

[@michaelspanier1235]

Hi from Germany, you will get completely the airbubbels out If you drive the motor hot and turn the heat sensor a half turn out, you will hear ffffft so no Troublecode P0128 anymore and you will see in display the temperature is in the middle of the field.

[@juviamsp8896]

my h3 hummer 08 is skeeting coolant from the bottom of the fan. what can it be

[@AutoRex101]

+Juvia MSP Cracked radiator is very common on these vehicles. Do a pressure test, it makes the leak much easier to find.

[@32volcomestone]

I noticed the tip of the old radiator has broken pieces. Would you worry if they went inside the motor?

[@AutoRex101]

Since the flow direction is towards the radiator, the debris gets caught inside the top tank. The radiator fins are too narrow to allow anything large enough to be harmful to pass and continue into the motor. The debris stays with the old radiator.

[@Froztinc]

I have a H3 Alpha with the 5.3 and the fan shroud is completely different. There is a upper shroud and a lower shroud and i cannot figure out how to remove it. There's 0 information on how to remove this shroud i guess not many people have the V8

[@bethanydavenport843]

How the heck do you replace the transmission fluid

[@juviamsp8896]

my H3 hummer 08 temperature gauge Rises to 3/4 when it's extremely hot outside. I already change the temperature sensor the water pump the fan. my temperature sensor goes up when I'm sitting in idle to 3/4 but once I start driving it goes back down to 1/2. So my question is do you think I need to change the radiator ?

[@brendacassata9885]

I am having same issue! New radiator, fan motor from Chey dealership, new everything that goes w radiator but still same issue. An electric fan installed didn’t work ??! Can anyone answer our question????? Ty

[@brendacassata9885]

Juvia MSP Did u figure out what was wrong?

[@bjohns6021]

Had the same problem with my 2006 H3 so I put in a CSF 7061 High Performance Aluminum Radiator it resolved the temperature issue.

[@gohan9638]

@@bjohns6021 what problems did your have before? Was yours heatting up and going back down when you drove? If so putting that radiator worked you say?

[@gohan9638]

@@brendacassata9885 did you find the answer to your problem?

[@samochoa6733]

Dont you need to use Dex coolant?

[@bjohns6021]

Yes, GM normally asks for Dex Coolant in the H3

[@joeblow6303]

Someone is trying to tell me that when you pull the AC condensor lines, you have to recharge the system. It didn't look like it to me. Is that true?

[@AutoRex101]

+Joe Blow Only if you are replacing the condenser. If you are just replacing the radiator you don't have to bother with the refrigerant at all.

[@joeblow6303]

Thanks AutoRex, that's what it sounded like. I should've replaced the radiator myself. The repair shop said they weren't quick disconnect/sealed fittings. Getting railroaded on this one.

[@nnfefe9451]

The support tabs @8:00 should have been supplied, being difficult to buy online.

[@bartbarnett2811]

You shouldn't take your protective caps off until you get it in there it's to keep dirt and debris out. But other than that great video

[@karasimmons7543]

what

[@ozzy5368]

You didn't flush the coolant, replace the fan clutch or hoses. You also mixed coolants, a big no-no, especially with Dexcool. That's going to gum up the new radiator nicely....and will look brown. Lastly you didn't burp it properly, which is done with a special funnel in the filler neck.

[@55jorge02]

if its only the radiator that gets clogged he will be lucky, hopefully none of the engines ports get gummed or blocked. Then the whole head has to come off and cleaned out not to mention the engine block.