im in the same boat...07 h3 70,000miles and i replaced the radiator my self to save money, its been over heating here in CO. its under powered too..im soo sick of this in line 5 junk so im looking into putting a GM v6...any engine gurus out there with some ideas if this will work? will it fit is a big que.

 

Not sure what you can use.

Some 4l60e transmissions have interchangeable bell housings. I don't know if the H3s' does without further research.

If it is then you can change over to a 60 degree v6 housing and use just about any modern GM v6 since they all use the 60* v6 pattern.

Even then not sure what engine you'd use since most make less crank hp than the 3700 vvt. Even the L67 SC makes ~ the same power as the 3700vvt, same goes for the 3900 v6.

You'd likely be better off going to an LSx v8, or procharging your I5.

 

The 3.6L 60* v6 is a vvt motor, from caddy and 2010 and up camaro.

But it's very tall, and who knows if it would even fit, same goes for the high feature v6 engines.

 

??what is procharging?? and i think i read about a 3.3 v6 cadalac engine, they were going to put in the hummer. GM also had or still has a 4.4 diesel duramax they had for the hummer...about 8 grand. I wonder if they have the 3.3, that maybe able to fit ..so frustrting, I had a 3500 dodge ram 03 for well right up till last year and trded it in for this..such a dumm mistake...so the lack of power and the over heating is killing me

 

You are familiar with the alpha,overpowered v8,h3?

The alpha guys really seem to like them,great owner reports.

Maybe you should have got one of them.

Overheating can be fixed. I dont know of an ongoing problem there, have never heard of one.

My i5 h3 idles at mid point in 95 deg sunny hot days,NEVER overheated once.

 

A procharger is a belt driven super charger that mounts with your accessories. It will give the power and then some that you're looking for.

As also stated, you have the LS 5.3 v8 option aswell.

One thing you have to remember is you're over 4000 lbs so the 3700 vvt is not going to break any speed records, but nor is the 5.3 v8. At least not without some sort of power adder. Personally I like my 3700vvt. But understand it not the best thing out there. I can say I've never had trouble with it in winter, or in the woods. We got it for use as mostly a family car with benefits of a truck when needed. Plus it's safetly record and it's 5-star crash rating. Don't get me wrong I like loads of power too. But I knew going into my purchase of my 08 H3 that it was'nt a super truck show stopper..

 

I purchased an H3T Alpha with just over 60k miles about 2 months ago. This past week I noticed my truck was draining radiator fluid but I thought it was due to the recent oil change (non-dealer) where they tried to sell me everything under the sun. Figured they just overfilled it. Anyway, after the trans started slipping I became a bit more concerned and took it to a GM dealer.

It appears that the trans cooler porton of my radiator has cracked/busted and now my trans fluid and radiator fluid have become intermixed. We assumed it would all be covered under the 100k mile power train warranty so I left it with the dealer to repair while they gave me a rental.

Just got a call from the service manager, it seems they will be rebuilding the transmition under warranty but GM declined the warranty on the Radiator. Said it was not a part of the power training, but just cooling for it... kinda like an alternator isn't covered under the powertrain warranty. All totaled the radiator replacment is gonna run me about $700 ($400+ radiator, $200+ labor and coolent).

I've gone ahead and agreed to the work so it can get done. However, I am thinking I will go back after the fact for reimbursement. I'm just afraid to push the issue right now as they may come back and say the radiator wasn't under warranty and that's what's called the transmition failure and therefore wouldn't cover anything.

Comments?

(Please excuse the spelling/grammer... in a hurry.)

 

Got mine back today with what appears to be the new design in radiator. I must also point out that I paid $0
I did not settle for the 10% off or the 15% off, in fact I told them they keep the truck and I'll let the bank know where they can get it. It was 7 days exactly with of course a weekend thrown in there.
I escalated up to a district manager before she OK'd this.
Just as the others have said, DO NOT take NO for an answer, especially if your crack looks like those in the pictures. For what it's worth though, they did say that if it ever became a recall or something like that, then the person could get reimbursed if they already paid for it.
The unit they put in would have been $894 out the door, so fight them on this.

A huge thanks to outerextreme for his inspiring write-up as well as taking the time to discuss his issue with me on the phone. I can guarantee had I not seen this thread or that post especially, I would have eaten this one.

Sidenote*
I had mine tuned and it has some rocking power now, especially when trying to get on the freeway.

Stang

 

So it looks like we are dealing with two issues here. The most common sounds like stress cracks and the lesser being the trans cooler leak.

To me, the radiator is poorly engineered which could result from the manufacturing process or the original technical design. I'm assuming the technical design came from GM/Hummer but the radiator is manufactured by a third party.

That leaves an interesting delima, who's at fault? Of course, as a Hummer owner that's really not my concern. I will expect Hummer to stand by their product and if they determine that their 3rd party is at fault (poor workmanship, bad manufacturing process, modification of design specification during manufacturing, etc.) then GM can cover the cost of repairs and pass those cost on to the manufacturer. If it's the technical design (which would include material specifications, stress tolerances, etc.) then it would be totally GM's burden to bear.

I can see a difficult lawsuit/mediation here should these cost ever reach the point of 'boiling over'. (hah.. get it... boiling over!! damn I'm funny). But again, not my problem. Once I get my truck back and I will pay what I need to pay to get it fixed right, I will be going to GM/Hummer for reimbursement.

I did speak with the service manager yesterday and he did not know if there was a different part number on the new radiator compared to the old one. If there is, then it would be a very strong indication that a problem was identified and corrected in the new version. Of course, it could be that the problem corrected in my radiator was for the crack and not for the trans cooling issue so it may not be the full proof I need.

I have already decided that once I reach the 100k mile warranty limitation I will be installing an after market transcooler that doesn't run through the radiator.

 

Stang5_0, I am glad to hear you stuck with it on GM paying for a new radiator and didn't back down. There is no reason we Hummer owners should have to pay for new radiators. If you look at the top portion of the radiator where it was cracked on the old one you should see vertical lines about an inch to an inch and a half apart. Those are where the new style radiator is given extra strength to prevent cracking. Once again glad you got it done and didn't pay for it.