1/4 vs 3/8 vs 1/2 drive ratchets and sockets. When to use which? (1 Viewer)

[Dirt Ferguson]

I've read some wrenching forums where people say 1/4" drive for everything interior, 3/8" for everything under the hood and 1/2" drive for everything under the vehicle. But I've always wondered if there's a set of guidelines outside of that. Obviously wherever you can fit the ratchet matters and you don't want to overpower a stuck bolt with a big wrench and break it off.

Any thoughts here?

Another idea I've been pondering relates to an OTRAMM video I was watching where he was doing a head gasket job on a 1FZFE. Sometimes he was zipping out bolts with an impact, other times he was breaking them free with hand tools.

What do you guys think?

 

[Mudder]

It depends on the ratchet. For instance I use the Milwaukee 1/4 and 3/8 non-fuel and they ar weighing 5 ft-lbs of each other (30 for the 1/4 and 35 for the 3/8). The fuel line they both are 35 ft-lbs of torque.

When it comes to heads or any type of surface that I want to remain true (exhaust manifolds or intake manifolds as well) I do it by hand so they are undone evenly and have a low chance of warping.

 

[sodafeld1]

It's almost a philosophical question that one. Nice one.
Pro mechanics working against time for money simply do it as fast as possible, which is not necessarily best practice.
It would cost a bomb to pay a mechanic to restore an old car, if working fast on old bolts there is good chance to break them.
Videos performed by pros are guidelines only, whilst working on the video they would be constantly double backing on themselves from usual practice and slowing down to step by step and explaining it, so they lose their flow. So what tool they are using for the video is not necessarily how they would be doing it normally. It is observant of yourself to be watching which tool they are using.

I do like the rough guide line you stated above.

Personally for me I use the smallest tool after finger tight at the start when installing new / reco parts then use the torque wrench if needed. I like my deflecting beam torque wrench as they do not require re-calibration too often, if ever. Good design, last a lifetime.
I use my 1/4 inch ratchet for lots of things at the start of installation, personal preference. It is light, compact, fast and elegant, fits in everywhere others don't. Sockets are compact too, in one place and handy. Fits in my pocket if I am interrupted and have to do something else at short notice. Go up in size if needed.

For undoing I use my cordless ratchet most often as it is fast, if I am familiar with the bolt or nut and has been off and on in memory. But unknown seized looking bolts easy does it with 3/8, bit of heat and wd40, patience and cycles of this process does wonders. The 1/2 inch is used plenty too but good chances you shall break the bolt with that one, so gently does it. Always a little sad to break a bolt!

It is nice to grow the affinity with your car.

One of my most frequent hard to reach bolt and nut are driveshaft yokes. Just go straight for the 1/2 inch. Often requiring a deep throat socket, extensions, ring and open ended spanner, extension tubes which fit over the spanners. Torquing them can be a little pia.

The other is the rear bolts and nuts of my 2h injection pump, they are simply dogs to reach and torque. Have to use 2 sets of unis on extensions. But you don't have to that too often one would hope. Bell housing is tricky in car too.

Not that I am a pro, but over time I have grown to have some favourite tools for sure. Irresistible discussion.

 

[Malleus]

I agree with a lot of what @sodafeld1 said. I don't have any electric powered tools; all mine are either air or hand operated, so I can't comment on those.

I use 1/4-inch drive sockets for fasteners smaller than 10-mm or 3/8-inch, simply because that's the drive limitation. Yes, I know there are adapters, but I don't like using more pieces than I have to. My tools have a habit of hiding from me when I let them out of their drawers. The fewer there are out, the fewer I have to keep up with. My 3/8-inch drive limits are, generally, 10-mm to 14-mm, or 3/8-inch to 1/2-inch. Anything smaller gets 1/4-inch drive and anything larger gets 1/2-inch drive. Unless it has a torque specification over 100-lb·ft; that gets into 3/4-inch drive territory. Anything over 350-lb·ft get into 1-inch drive range. And some bolt/nut sizes dictate which socket drive will be readily available, so there's that to consider.

Bolts that I know are expensive, like head bolts, get loosened by hand, so that I can feel them as they turn. Less breakage that way. Cheap bolts, like the ones holding the intakes or exhaust manifolds get an air wrench, because I either doubt they'll break or can easily fix them if they do. I do have one 12-mm 1/2-drive deep well socket - for the drive flange nuts, because I loosen the cone washers with an air hammer, and I already have the tool in my hand.

Your rules of thumb are generally OK, but you won't get the seats, or seatbelts, out of a Land Cruiser with 1/4-inch drive gear, so there are exceptions. Most of what's on the underside of the truck is large enough, or are torqued high enough, that you need 1/2-inch gear to remove it. One exception are the woefully undersized (6-mm) screws holding the felt retainers on the rear side of the 80 series knuckles. Try to remove them with anything larger than a nutdriver and you'll break them.

 

[Dirt Ferguson]

Great point about removing the seats and seatbelts @Malleus . I have taken out all the seats in the past and I definitely went with a 3/8 tool for that job.

I also like the input re the size of the bolt determining the size of the tools to remove it.

Well-thought out points from everyone. Much appreciated.

 

[ntsqd]

I tend to use a 3/8" for everything except the big stuff although I have been using a 1/4" more lately. I make the call by the expected torque required, not the size of the bolt. Those two don't always go in lock-step with each other.

Deflecting beam torque wrenches are my go-to std. The Top Alcohol Dragster that I used to crew on lost a couple races and engines due to a faulty clicker torque wrench. It had not been mistreated, it was always backed off to zero when put away. It just went out of calibration over time and that bit us. The engine shop that I later did fab work for had two clickers for their Assembly room that they keep in near constant rotation. One was either about to go out for calibration, out for calibration, or just coming back from calibration.
Just easier on my peace of mind to use a beam instead.

 

[PIP]

It may not really apply to the discussion here, but keep in mind 3/4", 1" and larger drive tools are needed for the bigger stuff you can run into.

 

[PAToyota]

I make the call by the expected torque required, not the size of the bolt.

Yes. Over time you get a feel for what is going to be required. Sort of the same as feeling whether you need a wrist click, elbow click, or shoulder/back click when applying torque.

Often I'm using a larger wrench to break something loose than I'd use for reassembly, when I want to have more "feel" for how tight I'm putting it back together.

Access also enters into the equation where a larger wrench just isn't going to fit.

 

[ntsqd]

I use the Pinky-Pain method, but yeah.

 

[rick_d]

undefined undefined | Matco Tools

www.matcotools.com

Use this all the time. 3/8” has been preference for decades.
I have both 6 and 12pt snap on shallow socket sets (since 1986!) and matco advanced deep impact (which are thin wall)
I have a 1/4” drive for the odd sub 8mm head.
1/2” for busting things off or bigger suspension needs. All shallow sockets except 2?
Click type (proto and matco) are fine for any job on a land cruiser. I have a dial snap on for preload.
A good set of extensions some with wobble type mixed in. (i dont use straight universals and universal sockets were a waste)

If you have air/electric use for disassembly and always hand for re assembly.

 

[cruiserpilot]

If you really want to learn, go to back of any Toyota Service Manual - at the bottom of the list
Standard Bolt Torque Specs and learn what load or torque limit is for each sized bolt. Then look at
torque limits on each specifically sized Torque Wrench. 1/4" is usually in inch/pounds
3/8" is usually 20 - 100/120 foot/pounds and 1/2" Torque Wrench is for 50 - 200 foot/pounds.
(My apologies to our purist metric users, I still can't translate into NM in my head )

Electric tools, we all know electric tools provide massive torque right from the get go. IF you use electric
either use hammer or clutch and know the difference. I run my 10 and 12 mm bolts using my 18V drill
BUT I always have low clutch setting ( never drill/screw setting ) so the drill clutch stops low torque and I
generally never over torque or twist bolts off.

I love air tools. 1/4" air ratchet is all you need to generally dismantle the interior of a 60. I know, done it
3 times. But air pressure is key. big difference between 95 psi and 120 psi.

1/2" impact air tool - Tire shops live and breathe these things. So common sense nothing inside wheel hubs
would ever use a 1/2" anything.

We all have preferences and I use the full gammit of available new and old tech.
Basically, lots of penetrating oil. If something doesn't move it's probably not because you aren't using enough
force. Ask every single person on this forum who's stupidly aggressively broken an exhaust stud off because they
didn't follow that rule??!!

My 0.02