Good Penetrating Fluid For Bolts For Rusty Suspension Parts?

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EddieC

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I am looking for suggestions for effective penetrating fluids to used on rusty suspension bolts.
The bolts go through bushings (rubber?) so compatibility would be useful but that bushed parts can be replaced if necessary to get the bolts out.
 

OR VietVet

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Best I have used:

 

petethepug

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Kroil was the 1st one that popped into mind for me. That’s the ship that broke a bond on a crank bolt for me. It took two weeks, occasional heat and a 6 foot cheater bar.

Your lucky it’s suspension parts because you can soak ‘n drive to allow the penetrant to soak in as the parts move.
 

petethepug

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If you do live in a rust belt or local mountains, marine grade products are your friend. Especially marine grade grease in and on the exposed ends of bolts. The stuff sticks like a combination of peanut butter and marshmallow cream with staying power.
 

j91z28d1

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you will open a can of worms with this one. I've never seen mechanics argue more about one thing than which is the best lol.

I've used about 10 different kinds and can't honestly say one has ever been noticeable better than another. there's one that gets cold when you spray it, that might help in some cases of you can't get a torch on it.

I did see a paper floating around work years ago that on the 60s the military came up with the best being a mix of acidtone and automatic tranny fluid. I don't remember the ratio they mixed them at thou. never got to try it
 

strutaeng

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Ya, this is probably as debatable as "what brand of engine oil is best?"

WD-40, PB Blaster, Liquid Wrench and even Silicone spray all have worked well for me. This is simply what's available locally here. I did experiment with the ATF/Acetone 50/50 and worked very well as well.

Several years ago I bought a gallon of PB Blaster but my wife complained everytime I used it about the smell. It DOES smell pretty nasty. I like Liquid Wrench because it foams up and seems to get better coverage. Last time I was as Summit Racing I picked up a gallon of WD-40 so that will probably last a lifetime

We don't really get severe corrosion around here, except for exhaust manifold bolts. Broken bolts are going to require drilling them or welding something to them.

Years ago I was removing the transmission on my 99 Silverado NBS. Someone must have stripped the oil drain pan bolt at the shop. Vice grips, screw extractor and everything else failed. I tried an entire afternoon. I finally got tired and dragged out my welding leads and crawled underneath and STICK welded a big 3/4" nut...out came the bolt. I wasn't even asking it if it wanted to come out by then, LoL.

And if you really wanted to see which one did better there's this scientific test:

:)
 

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