I'm going to be climbing under the car really soon to change out the old stock cats. I have:

A nice long-handled 1/2" drive socket wrench
a ~6" extension (maybe 8", not totally sure)
a 3" extension
one swivel attachment
Standard / ordinary wrenches

I will be picking up a slotted wrench of some sort to remove the O2 (wideband) sensors tomorrow, if they carry it at autozone. If not, I'll be hitting up the internet. Any suggestions for this?

So that I don't waste my time, anyone with experience doing this themselves can tell me if this is enough tools?

I am worried about being unable to reach the upper bolt on the top of the cats.

Also, how hard are these rusty bolts to remove? Easier, as hard, or harder than removing wheel lugs?

Thanks in advance

 

wd40 everything first. i just use crescent wrench for sensors and have never had any problems. the longer the extension, the better for access thru top of engine bay...i'm thinking 15" at least. harder than lugs...less leverage.

 

Yeah I think you may need more extensions. I probably bought up to 2-3' of extensions but I can't remember how much I had to use.

 

I used 30" of 1/2" extensions to go through the engine bay. Seemed about perfect. Crescent wrench will do fine for the 02 sensors. Liquid Wrench on the bolts, WD-40 didn't cut it for me. Hmmm, i'm trying to remember the size of the factory bolts, 13-14 mm I think.

 

Wait, so you don't think I can get to the top bolts through the bottom of the car??

Ugh! Well, looks like I'll be giving it a try with the swivel connector....


I don't really feel like buying 30" of extensions unless necessary.....those stupid simple pieces get expensive


Yes I already have liquid wrench, not to mention some high temperature anti-seize for the new bolts and O2 sensor threads. And new gaskets, yadda yadda yadda

By the way thanks for the tip that crescent will work for the O2 sensor

 

don't try to get the top bolts from the bottom. its a laborious exercise in frustration. trust me, from the top is the way to go.

 

i was able to remove the top bolts from underneath the car. reaching them from underneath is not much of a problem. the problem is that you have limited space for the wrench to travel so you have to make lots and lots of small turns. liquid wrench is definitely key. with the Z i was able to remove the 02 sensors with a crescent wrench, but it was pretty difficult. for my friends wrx i got an O2 sensor socket to remove the O2 sensor, and it seemed a lot easier. and i was able to get the o2 sensor socket from autozone. you can rent it, so you pay when you take it and get refunded when you return it.

 

Sigh.... looks like I'll be ordering a few feet worth of extensions on harbor freight. These craftsman extensions are $$$$$$$$$

Thanks guys.