Hummer h2 2007 -having issues
 

have had my H2 since 2011. Its an 07. Recently took mine for a 3 hour drive to the mountains in New Hampshire & it was running very bogged down. I had the pedal to the floor and it would barely reach 50 MPH. finally it would kick in but would immediately bog back down. It keeps happening. Fast forward to two week later: It worse than ever. of course it wouldnt do it for my mechanic. Finally today was the last straw. check mass air flow sensor, check the cats, removed the cats. not clogged, checked fuel pump, totally fine.... replace plugs and wires totally fine....drained and refilled crankcase with premium oil replaced k & N filter had a throttle body cleaning mass airflow cleaning....it still bogs so bad. 20 mph on back roads.... however when my mechanic took it out an put in in tow mode he said it ran pretty good.... I had a transmission put in last september -not rebuilt it was a newer used Escalade tranny. It ran great after.....
So not my question is do you think its the torque converter in the tranny? I am beside myself as I cannot handle another expense...
any thoughts? the tranny is not under warranty ...... someone save me
thank you cindy

How much $usd$ have you spent on attempt fix? Also, did you ever use top tier fuel?

any codes popping up?

Welcome to HF

You spent a bunch of $ on things that likely have zero relationship to your problem. If you want help you are going to have to do better that "running very bogged down" as I can't speak for all, but I have no idea what you are talking about. Like, what kind of RPM are we talking about? If your trans is having issues, your motor will still run just fine as the trans slips.

I would never buy a replacement used trans, much rather rebuild the trans I have with some top quality HD aftermarket parts. So, the $64 question, when was the last time you changed the trans fluid & filter? Pull the trans dip stick, and inspect level and quality, wipe it on a clean white cloth and post a pic of that here.

To me, bogging is when there is a reduction in expected RPM, perhaps a knock or ping too?

Scan all systems for any stored code. Post whatever you find.

New Hampshire :) I have a vacation home way way up in Pittsburg. You definitely need to find a competent mechanic - I don’t think this should be that hard to pin point where the issue is - driveline or engine. Once that’s figured out surely someone can find the cause

If it's really bogging down it's gonna be fuel or air
 

Supposedly clogged egr could also cause issues. Did u try replacing fuel filter? Could be clogged. Or fuel injectors. I'd bet fuel filter or injectors as likely culprit. It's hard to mistake a slipping tranny for bogging down so I'd doubt that.

Only 2003 has a separate changeable fuel filter. 04 and up just have a screen on the fuel pump itself inside the fuel tank.