Need advise on a torque wrench purchase. I am going with CDI. I cannot make up my mind on wether to purchase a 3/8 or 1/2 inch drive. The range I need is 20-150 ft/lbs. I know that most are going to tell me that I can just get a 3/8 inch drive and use a 1/2 inch socket adapter if needed but some will say that the torque accuracy then also changes. I am mostly using the torque wrench for Brakes, Motor mounts, shocks, struts, and suspension parts that include lower and upper A arms ( double wishbone), control arms etc. Please advise
Torque Wrench 3/8 or 1/2 drive
- Thread starter Gito
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3/8 are more practical on small cars with a range of 20-80 ft lbs. Heavier work is normally for a 1/2 drive of 150 or 250 ft lbs. The 1/2 drive is not accurate at 20-30 ft lbs but can torque an axle nut.
Heavy suspension torque, 1/2 is the way to go.
Everything smaller that 19 mm, a 3/8 will do great.
I work on heavy equipment and have every torque wrench you can think of from 1/4 - 3/4 drive. The middle to upper end of the scale is more accurate than at the bottom.
Heavy suspension torque, 1/2 is the way to go.
Everything smaller that 19 mm, a 3/8 will do great.
I work on heavy equipment and have every torque wrench you can think of from 1/4 - 3/4 drive. The middle to upper end of the scale is more accurate than at the bottom.
Gito,
If you are going to do a large amount of work on autos, then you will need both 3/8 and 1/2 style. I actually just had to buy a 3/4 inch torque wrench cause I needed to torque an axle lug nut to 214 ft lbs.
My 3/8 inch is a husky clicker and it's a nice wrench. My other 1/2 and 3/4 are the cheap harbour freight style. I'd love to get a better quality set of 1/2 wrenches, but for the price they work good!
Regards, JC.
If you are going to do a large amount of work on autos, then you will need both 3/8 and 1/2 style. I actually just had to buy a 3/4 inch torque wrench cause I needed to torque an axle lug nut to 214 ft lbs.
My 3/8 inch is a husky clicker and it's a nice wrench. My other 1/2 and 3/4 are the cheap harbour freight style. I'd love to get a better quality set of 1/2 wrenches, but for the price they work good!
Regards, JC.
You really need 3 or 4 if you do everything on the car yourself, stuff like plastic plenum's throttle bodies, some transmission work, oil pans, etc require inch ib or low lb·ft.
I find a 1/4" drive is best suited to this sort of work.
I use 3/8 drive mostly for manifolds, aluminum housings and a few other things that really require a torque wrench and on motorcycles.
For wheels and the most of the work you mention definitely go with 1/2" drive up to 150lb·ft don't go with the larger 250lb·ft models as their accuracy may not be there in the lower ranges.
CDI is a quality tool and a good choice IMO.
I find a 1/4" drive is best suited to this sort of work.
I use 3/8 drive mostly for manifolds, aluminum housings and a few other things that really require a torque wrench and on motorcycles.
For wheels and the most of the work you mention definitely go with 1/2" drive up to 150lb·ft don't go with the larger 250lb·ft models as their accuracy may not be there in the lower ranges.
CDI is a quality tool and a good choice IMO.
Originally Posted By: Gito
Need advise on a torque wrench purchase. I am going with CDI. I cannot make up my mind on wether to purchase a 3/8 or 1/2 inch drive. The range I need is 20-150 ft/lbs. I know that most are going to tell me that I can just get a 3/8 inch drive and use a 1/2 inch socket adapter if needed but some will say that the torque accuracy then also changes. I am mostly using the torque wrench for Brakes, Motor mounts, shocks, struts, and suspension parts that include lower and upper A arms ( double wishbone), control arms etc. Please advise
Sorry, meant to type "advice" at beginning of sentence
Need advise on a torque wrench purchase. I am going with CDI. I cannot make up my mind on wether to purchase a 3/8 or 1/2 inch drive. The range I need is 20-150 ft/lbs. I know that most are going to tell me that I can just get a 3/8 inch drive and use a 1/2 inch socket adapter if needed but some will say that the torque accuracy then also changes. I am mostly using the torque wrench for Brakes, Motor mounts, shocks, struts, and suspension parts that include lower and upper A arms ( double wishbone), control arms etc. Please advise
Sorry, meant to type "advice" at beginning of sentence
I'd go 1/2" for that range. My Craftsman 1/2" clicker-type covers that range nicely.
Gito - in your range, get a 1/2". Most 3/8" won't go up to 150 lbft and for suspension parts, you're going to be in the 40-90 lbft range, generally above the capacity of a 3/8. You will appreciate the longer length of the 1/2" as well when doing larger bolts at higher torque. You can always add a 3/8" later, it's more of a spark plug/delicate parts kind of tool.
I have both. I use the 1/2 more but certainly use the 3/8
There are a few different models.
for example there is a craftsman
3/8 25-250 INCH/LB
3/8 10-80FT/LB
1/2 20-150
looked up CDI
looks like you would need at least 2 to be well covered.
if you use them for a living probably need 3
for me I'd get the big 30-250 ft/lb
and the 3/8 5-75ft/lb
and if needed the 1/4 20-150 in/lb
they also make a
3/8 30-250 in/lb
3/8 10-100 ft/lb
and a few more models so really you have alot of options.
to pick out ranges that work well for what you are doing.
Keep in mind if you use clicker type
and have to use the lowest part of the range.. they dont click very hard..easy to miss.
ie using that 30-250 ft/lb at 30 isnt good.
or using the 10-100 at 10
also trying to use the short 3/8 5-75 at 75 will be like hercules
for example there is a craftsman
3/8 25-250 INCH/LB
3/8 10-80FT/LB
1/2 20-150
looked up CDI
looks like you would need at least 2 to be well covered.
if you use them for a living probably need 3
for me I'd get the big 30-250 ft/lb
and the 3/8 5-75ft/lb
and if needed the 1/4 20-150 in/lb
they also make a
3/8 30-250 in/lb
3/8 10-100 ft/lb
and a few more models so really you have alot of options.
to pick out ranges that work well for what you are doing.
Keep in mind if you use clicker type
and have to use the lowest part of the range.. they dont click very hard..easy to miss.
ie using that 30-250 ft/lb at 30 isnt good.
or using the 10-100 at 10
also trying to use the short 3/8 5-75 at 75 will be like hercules
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Craftsman has both sizes for $39.99 on sale. The sale has been on and off.
How often will you be going over 75 ft/lbs. ?
If not that often, go with 3/8 drive.
If not that often, go with 3/8 drive.
I have a 1/2" 50-250 ft*lb wrench for lug nuts (90% of what it gets used for) and other higher torque applications, and a 3/8" beam type for
I came to the conclusion that 1 was not enough.
I came to the conclusion that 1 was not enough.
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Originally Posted By: Gito
Wheel lug nuts. Own 5 cars which see the road often.
For wheel lug nuts, 1/2 drive is better.
How long is that CDI torque wrench? It needs to be at least 18 inches long for tightening lug nuts.
Wheel lug nuts. Own 5 cars which see the road often.
For wheel lug nuts, 1/2 drive is better.
How long is that CDI torque wrench? It needs to be at least 18 inches long for tightening lug nuts.
For torquing lug nuts, you might consider a different torque wrench. The P.I. split beam with its flex head is ideal for torquing lug nuts. The flex head allows the handle to clear the tires without needing such a long extension. With a deep socket and the P.I. split beam, you may not even need an extension. But with a non flex head and a deep socket, you're going to at least need a 3 inch extension, if not longer.
Originally Posted By: Gito
I can just get a 3/8 inch drive and use a 1/2 inch socket adapter if needed but some will say that the torque accuracy then also changes.
wut
Torque wrenches are most accurate in the middle of their range. As you've stated, most of your jobs will require tightening of smaller fasteners. Get the 3/8" CDI wrench to work within the 'sweet spot' for these more critical parts. For the once a month lug tightening get a Harbor Freight 1/2" wrench. I've personally tested the 1/2" HF wrench on my job's calibrated torqe transducers and it bests the +/- 4% stated accuracy repeatedly.
I can just get a 3/8 inch drive and use a 1/2 inch socket adapter if needed but some will say that the torque accuracy then also changes.
wut
Torque wrenches are most accurate in the middle of their range. As you've stated, most of your jobs will require tightening of smaller fasteners. Get the 3/8" CDI wrench to work within the 'sweet spot' for these more critical parts. For the once a month lug tightening get a Harbor Freight 1/2" wrench. I've personally tested the 1/2" HF wrench on my job's calibrated torqe transducers and it bests the +/- 4% stated accuracy repeatedly.
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