Advice on undercarriage rust treatment?

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@bobr1 Get some Ospho (Phosphoric acid blend) from Ace/Home Depot and spray it on. It's a rust converter that'll convert iron oxide into iron phosphate... turns the metal black with some white powdery residue. Wash that stuff off and you can paint/treat metal afterwards, if you want. Use precautions when applying. Also, phosphoric acid can etch concrete.

Give it a try and first test it on the skid plate.
 
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Yes. You can get it in a gallon and in bigger size containers.

Check out the infamous thread on the Raptor Forums.... T9, Amsoil HDMP and Fluid Film were the top three products all having similar performance.

I've used all three over the years and they are all fantastic. T9 goes on alot smoother than Fluid Film, it's clear, and once it cures you basically don't even know anything is on there. It's like 100/gallon but I used something like 15oz. in a spray gun to do my brother's IS-F so it's really not that terribly expensive. Less than $20 to do an average size undercarriage.
Wow nice to know


I have use T-9 on my bicycles (and sometimes) on my motorcycle chains and cables for years

Nothing works better kind of quality..
 
@bobr1 Get some Oshpo (Phosphoric acid blend) from Ace/Home Depot and spray it on. It's a rust converter that'll convert iron oxide into iron phosphate... turns the metal black with some white powdery residue. Wash that stuff off and you can paint/treat metal afterwards, if you want. Use precautions when applying. Also, phosphoric acid can etch concrete.

Give it a try and first test it on the skid plate.
Awesome thanks for the help! I think I will give this a try first and use the skid plate like you mentioned.
 
T-9 for sure. With that rust problem, I would immediately treat the entire underside and
hope for the best. I use it once a year on mine even though I live in the "desert" of Oregon.
 
T-9 for sure. With that rust problem, I would immediately treat the entire underside and
hope for the best. I use it once a year on mine even though I live in the "desert" of Oregon.
Do you use the cans or did you go ahead an use the gallon jug. And how many cans did you use or how many applications from the 1 gallon do you get?
 

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