Can't break rear diff bolts.

Properly seated hex/socket with an impact wrench.

Quick motion with breaker bar.

 

Penetrating oil and in particular PB blaster are the most laughable gimmicks in the auto industry. They simply don't penetrate. Great when you can get them on the threads, but rust welds are pretty impenetrable.

 

I don't I've seen anything KROIL can't penetrate. It even works on the clamped ends of the can it comes in. As far as your diff fill plug is concerned, a good 6pt impact socket and a 1/2in impact and it'll come right outta there.

 

I took it to the dealership, politely asked for them to torque it to factory spec, they did it for free as it should have been that way.

 

Good 6 pt socket on a breaker bar then slide your floor jack handle on it and it will easily come off.
Or as stated a good 1/2" impact if the torque rating is fairly high.

 

This is the first video of his I've watched in at least a year because he used to only use a sample size of 1. I'm so glad he started using a sample size greater than 1. Also, that ATF/Acetone looks delicious!

 

Sometimes his style of repeating the product names over and over gets annoying, but I appreciate his practical attempts to review many tools and products.

 

I had a similar struggle with a front diff drain bolt years ago. I almost destroyed it trying to take it off. I tried every trick, heating it, penetrating oil (not sure how that's supposed to work when there is a metal gasket design to stop oil from leaking), using a cold chisel to try to turn it, putting a floor jack under the breaker bar for more torque, etc. I rented a basic corded electric impact and got the best fitting 10mm Allen adapter I could find, and it took it right off in 2 seconds. Now I own a cordless impact, and I don't think I could work on rusty Toyota trucks without it. If you can't afford cordless, there are cheap corded impacts probably around $50 that will do most of what you need. There's just something different about impact that you can't really replicate with hand tools.

The only thing more effective than impact is welding on the offending fastener. Something about getting it red hot loosens it up, even though hot metal expands so you would expect it to get tighter. I guess it gets hot enough to break any rust and soften the bolt. I've had mixed success with heating bolts (and/or the surrounding area) with a propane torch. Sometimes it works, but it's hard to get enough heat into an area to make a difference. Usually welding is a last resort after you've rounded off the head, but in my limited experience so far (just recently got a welder) a stuck bolt will come out easily after welding something to it.

 

If you don't have an impact wrench, use a floor jack to jack up the truck via a breaker bar (jack pushing up on the breaker bar handle) attached to the fill plug. The plug will move before the truck does.

 

This new formula actually works pretty good. It’s not just WD40 and it worked great when removing rusted out lower control arm bolts.

 

Youtube is making us all dumber.

 

Broke down and got an impact. Came right off. Torqued fill and drain back to the correct 36 foot pounds so hopefully it's much easier to break when the next fluid change comes around. Thanks everyone for your input!

 

Sweet and you got a new tool! Bonus.

 

For the most part, yes. And I agree PB is garbage. But there are some penetrating oil's that chemically react with rust and break it down. Free All and (to a lesser extent) Kroil work best IME.

 

All the fluids looked darn good. I could see nothing that would indicate that they were at the end of their lives. I did both diffs, transmission, and transfer case.