just picked up a 2003 H2 with 57K miles on Aug 13 last month... history was clean no accident or airbag deployment... and this car was serviced timely at the GM dealers...

i looked under the body... and i could see the typical rust appearing under some of the underbody coating... this car has its underbody coated with a Zeibart like coating.... so i decided to removed as much of the sticky tar-like coating with a heat gun... i can see clearly where those spots where rusting... as it would should a pop up or flaking dried coating... those scrapped off easily with a hand scrapper and heat gun ... decided to go with KBS coating rust seal steps....but i bought a gallon of Phosphoric acid... as its the same stuff in Step2... just stronger from the local HD

dropped the bumper.. and the rear bumper frame... sanded it..... derust both pcs covering it in Phosphoric Acid,keeping it wet for at least 12 hrs ... .. flushing it offf with a mix of simply green scrubbing .. sanding again with a angle grinder n wire brush... .... and coating in the acid for another 6 hrs with a brush and spray bottle.......

all the bolts and nuts were rusted..



how to remove the rust?..... sand them??.. scrub them???



Reaction of the acid on the bolts and nuts..




clean to bare steel


The rear bumper plate... this was heavy... as i am just a 135lb gal...

 

Rear Bumper Sub Frame... this was heavier... darn... at least 3/4 inch box type beams....needed 2 person

the cleanup with SimplyGreen first to get rid of soil .. dirt.. oil... grease......and started the grind down of the whole beam....



next up the same process.. coat acid .. grind .. wash... coat acid.. wash step1... took me another weekend...


weather was good today... sunny... at last sun... so started with the Anti Rust Coat.. Step 3...

the paint is self leveling .. so using a paint brush will bring out a good finish..

the steel bumper..exterior.. i would need to coat with a layer of topcoat tonight...


the Rear Bumper SubFrame...

 

now i have a question... after removal of these parts... this is the section which is difficult to reach without lifting the whole body off... any suggestion??

currently using my air die angle grinder with a wire brush attachment.. it allows to get into those hard to reach spots..or angle....

i guess i would need to go under the truck and work from there... gosh.. these are the times.. when i wished i had a car lift...

 

From what is seems like you are wanting to do it would honestly be easier to left the body off the frame. PITA but it would gain you access to EVERYTHING.

I absolutely never plan on getting rid of my 2 and one day will probably be taking on the same thing you're doing so it will last a lifetime!

Good luck.

 

yes... i am seeing the options i have.. to pour the Phosphoric acid into a spray bottle.. and spray on those inside area... there after..crawl under the truck.. with my cap and safety googles on.. use the small air angle grinder , nifty tool.. i liked the size of the tool....

 

i should have enough space..

 

hubby picked up a near new compressor for $120 ... this will aid me in using the angle grinder more... rather than the 6 gal carryaround unit... which only allows me 2 mins and it recharges

 

coated all the rear section frames... etc... even the suspension mount brackets was a pain to reach and pain... luckily i had blue nitrile gloves...and had on a old long sleeve t.... arms was all covered in the rust seal paint.... ....

i am left with the rear diff to sand /wire brush it...acid it and coat it....

 

a question, the rear disc brakes, there is the brake dust shield , one on each side ... its rusted out... and i would like to change them out... searched on the web on how to do that... but no pictures on a thread i found... anyone has done it before..and wouldnt mind exampling to me

SHIELD KIT. Parking Brake Apply.
2008 Hummer H2.
Stock Code 15949893
Manufacturer GM
Categories Brakes > Parking brake
Assemblies CK310,314 PARKING BRAKE ASM; PARKING BRAKE ASM; PARKING BRAKE ASM; PARKING BRAKE ASM (

)

 

i found this ... as close as i could find...

How to Change Brake Pads and Rotors on a general GM Disc Brake System | eHow