2010 Express 2500 cargo. 4.8 flex.

I'm gearing up to tackle pitman and idler arms. They're worn and I've got new tires on I'd prefer to not also wreck I'm going to buy a socket to take this off as it's one I don't have. A caliper measures out 1.294 inches. For metric, that's a hair shy of 33mm. 0.005" of excess. That's probably it. Which, 33mm, kinda odd. Though most of the vehicle I wrench were from countries that used metric originally. Maybe it's the closest size from old engineering definition when it might have been 1 5/16. Anyway, question is does anyone know for certain? Please and thank you.

 

American cars use 13mm often, because it's quite close to 1/2" (12.7mm). It wouldn't surprise me that when converting from inch to mm that they just went with the closest and not to what a Japanese or German standard would have been. Also, one of the things I like the most about GM is their "if it ain't broke don't fix it" attitude. It wouldn't surprise me if the shaft is still inch. My 1971 Blazer takes a 1-5/16" socket for the pitman arm.

Did some digging and it sure looks like it's still inch
https://www.gmpartsgiant.com/parts/g...ra2=&filter=()

 

While you are in there even if you don't replace your idler arm bracket you should look into putting a grease extension hose on it. Most often they wear out because nobody greases them because it's hard to see and get at. The zerk gets moved to by the sway bar frame mount making it now very easy to get to.
https://www.rockauto.com/en/moreinfo...08860&pt=13418

 

Great tip! I am doing both parts.

https://www.rockauto.com/en/moreinfo.php?pk=16574569

 

"Hey guys, just wanted to chime in, I replaced my 2022 Camaro's pitman and idler arms last weekend and I noticed the steering box nut size is 32 mm, pretty standard stuff, but if you're unsure it's always a good idea to double check your repair manual or consult with a pro if you're not comfortable with the job."

 

Can confirm. 33mm is pretty good.

 

Oh hmm. Not to spam the thread. But it doesn't look like I can edit the last post. In addition to the 33 mm, the job to do pitman and idler arms doesn't require much in the way of specialized tools. But I did buy a puller.

It's 1 3/16 opening. https://www.autozone.com/p/oemtools-...eId=6847576510

Which was a little tight. So I took a razor knife to the rubber bushings to get clearance. And lightening the bolts into the steering...rod? Needed to hold those in place with an 8mm socket and snug with a 21mm wrench. I used a flat ratchet. But a box wrench would work too. The rest, 21mm and lower sockets. Youtube videos for the process.