How to properly torque subframe bolts?
Thread Starter
MBWorld Fanatic!
Joined: Mar 2011
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2011 E63, 2013 CLS63
How to properly torque subframe bolts?
Hi guys,
So the subframe bolts are obviously very important and are one time use. I just dropped the subframe to drop the engine in my car and put the new engine on the subframe. I ordered the bolts brand new from the dealership.
I'm not very experienced with torquing properly and I realize that these bolts need to be torqued to spec, not just really tight.
Is the torque spec a torque number that you just dial onto one of those analogue torque wrenches or is there some angular aspect too. What I mean by that is that I've realized there are specs which state angles as well as torque figures. I'm not too sure about torque angle and what not. Can someone help with this.
By the way, apparently the torque wrenches come calibrated and you shouldn't drop them or hit them or they might go out of calibration. How do I know I've purchased a good accurate wrench and that it's never been dropped..... (I know I'm being paranoid but I really don't wanna mess with the subframe connection to the car as it's kind of important
)
Also, there's loctite on the original bolts; it would be a good idea to apply some right?
So the subframe bolts are obviously very important and are one time use. I just dropped the subframe to drop the engine in my car and put the new engine on the subframe. I ordered the bolts brand new from the dealership.
I'm not very experienced with torquing properly and I realize that these bolts need to be torqued to spec, not just really tight.
Is the torque spec a torque number that you just dial onto one of those analogue torque wrenches or is there some angular aspect too. What I mean by that is that I've realized there are specs which state angles as well as torque figures. I'm not too sure about torque angle and what not. Can someone help with this.
By the way, apparently the torque wrenches come calibrated and you shouldn't drop them or hit them or they might go out of calibration. How do I know I've purchased a good accurate wrench and that it's never been dropped..... (I know I'm being paranoid but I really don't wanna mess with the subframe connection to the car as it's kind of important
)Also, there's loctite on the original bolts; it would be a good idea to apply some right?
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From: Portland, Oregon
2019 Jeep Trackhawk, 2002 CLK55, 2014 911 Carrera
You are correct that sometimes a torque spec just calls for a number, other times it calls for a number and then an additional turn of x-degrees. Unfortunately I don't know the proper procedure for torquing your subframe bolts. Maybe someone else can tell us.
As for the type of wrench, you are also correct that the "click" type can become uncalibrated. The most reliable type are the old-fashioned beam type, but you have to use them correctly otherwise you can overtorque a bolt. Honestly, I think either one would work here. I would be more concerned if you were torquing engine internals.
As for the type of wrench, you are also correct that the "click" type can become uncalibrated. The most reliable type are the old-fashioned beam type, but you have to use them correctly otherwise you can overtorque a bolt. Honestly, I think either one would work here. I would be more concerned if you were torquing engine internals.
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From: New Zealand
If you are worried, just take the torque wrench to a reputable tool shop and they will recalibrate it for you. I don't worry with mundane things but would definitely get it done before torquing head bolts and other critical hardware.
Thread Starter
MBWorld Fanatic!
Joined: Mar 2011
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2011 E63, 2013 CLS63
Thanks for the replies guys.
I suppose they're not as important as head bolts but it's still the engine cradle. I just don't wanna be paranoid all the time and have it on my mind.
I haven't actually purchased a torque wrench yet, would any do or is a reputable brand better than a cheaper one?
From my research it seems that you set the torque, torque the bolt until it clicks, then you get that degree socket tool, put it on the bolt and then turn a number of degrees with a breaker bar. Is it that simple?
I just wanna do it right because I feel like it's my responsibility to have my car as safe and roadworthy as possible because if something goes wrong it could not only put me in danger, but others also. Better safe than sorry I guess. Sorry if I seem like a ****.
I suppose they're not as important as head bolts but it's still the engine cradle. I just don't wanna be paranoid all the time and have it on my mind.
I haven't actually purchased a torque wrench yet, would any do or is a reputable brand better than a cheaper one?
From my research it seems that you set the torque, torque the bolt until it clicks, then you get that degree socket tool, put it on the bolt and then turn a number of degrees with a breaker bar. Is it that simple?
I just wanna do it right because I feel like it's my responsibility to have my car as safe and roadworthy as possible because if something goes wrong it could not only put me in danger, but others also. Better safe than sorry I guess. Sorry if I seem like a ****.
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From: New Zealand
Yes get a good brand, I paid $150 or so for mine quite a few years ago. I have two made by teng tools https://www.tengtoolsusa.com/hand-to...-wrenches.html They should come perfectly calibrated from the factory and they suggest you do it every year. I have never had mine recalibrated as I did some headbolts soon after I got it and haven't done anything I consider that important since. They should come with a log book showing the actual and target torque and the date it was done.
I have the 40-200Nm and the 5-25Nm which almost covers anything you could need on a car. They have angular dials on the top so you can use them for angular torques too, of course I usually do what you suggested and just chuck a breaker bar on the socket and turn 90 degrees or whatever it might be. Yes the click is easily felt, seen and heard when you get to the correct torque, test it on a low torque setting on a large already tightened bolt and you will be very comfortable using it. That simple.
Of course I don't actually know the torque settings of the subframe, it should be in WIS.
I have the 40-200Nm and the 5-25Nm which almost covers anything you could need on a car. They have angular dials on the top so you can use them for angular torques too, of course I usually do what you suggested and just chuck a breaker bar on the socket and turn 90 degrees or whatever it might be. Yes the click is easily felt, seen and heard when you get to the correct torque, test it on a low torque setting on a large already tightened bolt and you will be very comfortable using it. That simple.
Of course I don't actually know the torque settings of the subframe, it should be in WIS.
Thread Starter
MBWorld Fanatic!
Joined: Mar 2011
Posts: 2,214
Likes: 29
2011 E63, 2013 CLS63
Yes get a good brand, I paid $150 or so for mine quite a few years ago. I have two made by teng tools https://www.tengtoolsusa.com/hand-to...-wrenches.html They should come perfectly calibrated from the factory and they suggest you do it every year. I have never had mine recalibrated as I did some headbolts soon after I got it and haven't done anything I consider that important since. They should come with a log book showing the actual and target torque and the date it was done.
I have the 40-200Nm and the 5-25Nm which almost covers anything you could need on a car. They have angular dials on the top so you can use them for angular torques too, of course I usually do what you suggested and just chuck a breaker bar on the socket and turn 90 degrees or whatever it might be. Yes the click is easily felt, seen and heard when you get to the correct torque, test it on a low torque setting on a large already tightened bolt and you will be very comfortable using it. That simple.
Of course I don't actually know the torque settings of the subframe, it should be in WIS.
I have the 40-200Nm and the 5-25Nm which almost covers anything you could need on a car. They have angular dials on the top so you can use them for angular torques too, of course I usually do what you suggested and just chuck a breaker bar on the socket and turn 90 degrees or whatever it might be. Yes the click is easily felt, seen and heard when you get to the correct torque, test it on a low torque setting on a large already tightened bolt and you will be very comfortable using it. That simple.
Of course I don't actually know the torque settings of the subframe, it should be in WIS.
So it's basically:
1. Torque to torque spec using torque wrench until click
2. Put on angular torque socket and turn X degrees
I usually do a pretty good job of things but for some reason I'm not confident in myself in certain things, maybe I just like to over complicate something not so complicated.
MBWorld Fanatic!
Joined: Aug 2011
Posts: 3,428
Likes: 288
From: New Zealand
Thanks for the input, I have WIS, I'll check it.
So it's basically:
1. Torque to torque spec using torque wrench until click
2. Put on angular torque socket and turn X degrees
I usually do a pretty good job of things but for some reason I'm not confident in myself in certain things, maybe I just like to over complicate something not so complicated.
So it's basically:
1. Torque to torque spec using torque wrench until click
2. Put on angular torque socket and turn X degrees
I usually do a pretty good job of things but for some reason I'm not confident in myself in certain things, maybe I just like to over complicate something not so complicated.
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Joined: Feb 2026
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2006 cls500
Hi guys,
So the subframe bolts are obviously very important and are one time use. I just dropped the subframe to drop the engine in my car and put the new engine on the subframe. I ordered the bolts brand new from the dealership.
I'm not very experienced with torquing properly and I realize that these bolts need to be torqued to spec, not just really tight.
Is the torque spec a torque number that you just dial onto one of those analogue torque wrenches or is there some angular aspect too. What I mean by that is that I've realized there are specs which state angles as well as torque figures. I'm not too sure about torque angle and what not. Can someone help with this.
By the way, apparently the torque wrenches come calibrated and you shouldn't drop them or hit them or they might go out of calibration. How do I know I've purchased a good accurate wrench and that it's never been dropped..... (I know I'm being paranoid but I really don't wanna mess with the subframe connection to the car as it's kind of important)
Also, there's loctite on the original bolts; it would be a good idea to apply some right?
So the subframe bolts are obviously very important and are one time use. I just dropped the subframe to drop the engine in my car and put the new engine on the subframe. I ordered the bolts brand new from the dealership.
I'm not very experienced with torquing properly and I realize that these bolts need to be torqued to spec, not just really tight.
Is the torque spec a torque number that you just dial onto one of those analogue torque wrenches or is there some angular aspect too. What I mean by that is that I've realized there are specs which state angles as well as torque figures. I'm not too sure about torque angle and what not. Can someone help with this.
By the way, apparently the torque wrenches come calibrated and you shouldn't drop them or hit them or they might go out of calibration. How do I know I've purchased a good accurate wrench and that it's never been dropped..... (I know I'm being paranoid but I really don't wanna mess with the subframe connection to the car as it's kind of important
)Also, there's loctite on the original bolts; it would be a good idea to apply some right?
