What is the worst mistake you made doing your own wrenching?

Nice. The transmission never did go out in that thing. I was surprised. I figured I ruined the parking pawl, but it held for as long as I had it.

 

Yeah, the last auto that I'm aware of that had forward and reverse gears next to each other was the pre-58 Chevy Powerglides...

 

When I was ~18 or so I managed to throw my truck into reverse while going maybe 40mph (was a '99 Prerunner)...I missed having a manual transmission like my previous car, and like an idiot (didn't know any better at the time), I thought I'd have some fun "manually" shifting my automatic from first gear on up using the shift lever. I went from 1st to 2nd...2nd to 3rd...3rd to 'D'...and 'D' to a terrible metal clanging/clanking sound that stalled the truck and caused me to have to pull over. I had pushed it up from D past neutral and into reverse, without thinking.
Luckily she fired right back up and I went on my way, but I never did that again lol. Didn't seem to cause any long term damage that I was aware of, though I only had it for another year or so.

Not one of my prouder moments but since we're all being honest in this thread, figured I'd get it off my chest...15 years later.

 

Years ago I was changing the water pump on my old pickup. One of the bolts wasn't coming out as easily as the others, so I really started wrenching on it. Bad idea, it sheared off about half way out. I was young and didn't have the skill set to fix that or the money to have the work done. It freaked me out because I thought for sure it would leak with only the other three or four bolts holding the new pump in. I just went heavy with the gasket maker around that bolt hole and it was fine. I drove it for a couple more years after that with no problem.

 

I was putting a new aluminum intake on an old SBC motor in my truck. Got the gaskets & permatex set with the manifold on. I grabbed a torque wrench & didn't realize it was Nm & not ft-lbs so I set it for what I needed without noticing. Got most of the bolts tightened down without any issues but then I snapped a bolt & somehow the head popped out of the socket, pinged off the hood & went directly down the distributor hole. I then spent probably an hour trying to fish it out with a telescoping magnet so I wouldn't have to take the intake back off

I got the bolt head out & chalked up as a lesson learned

 

This is why I take firearms apart with both hands inside a box or a Wal*Mart sac

 

I took apart my 10/22,( in my living room apartment) I even took the trigger assembly apart as it was gritty everywhere, soon as i got the safety out I hear a spring fly and another pin fly, hit the ceiling and hit the wall and fell behind the couch. I had to use a magnet to find the pieces...

 

1. Accidentally drained the transmission fluid when I was changing oil.
2. Accidentally installed an oil filter with two gaskets.
3. Intentionally cleaned the instrument cluster plastic cover with a paper towel.

 

That works great for metal parts I have had to do it myself. I have needed a plastic magnet sometimes too

 

I was working on an RF amp once, 1amp worth of 3,500 volts from the primary transformer went from the tip of my pinky finger to my my wrist that was touching the amp frame. Fuse blew, and it felt like my arm got run over by a semi for 2 weeks. Couldn't move fingers for a few hours.

 

I put a K&N intake on a truck. 20 min job, I've done several. Start truck, all check engine lights come on, truck shuts off. Check all OBD codes, cussed. K&N put one of their stickers in the intake tube, I didnt look inside the tube..... Pulled stupid sticker from throttle body with forcepts. All good.

 

yeah that would be nice if it worked for everything else also sometimes you just have to order new parts if you can!

 

I put decaf in the coffee maker.

Never had a really bad f up on my vehicles. But I don't do the hard stuff myself.

 

Wow. Dangerous. Military gear ? You were lucky it was your fingers that couldn't move and not your heart. Be careful !

 

Had a Model A rat rod with a BBC 454 and duel carbs. Tried to swap the duel carb tunnel ram to a single. Different ports on the heads so went back to dual carb. Mounting bolt ended up somewhere in the heads. Swear I heard it hit the ground. After a month of driving it found the bolt between the piston and the head....

 

I do not mind waiting on parts I order for upgrades but I hate to wait on replacement parts I lost or screwed up It just makes you feel like a dumbass everyday until they get here

 

That's not where I like to find missing bolts

 

I rebuilt the rear end on my old Suburban (first and only one I’ve ever done). I couldn’t get the pattern right so I decided it was fine. About 5,000 miles later it grenaded on me. $1200 in parts trashed.

 

Rebuilding diffs is not easy. Very difficult to get it right.