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Discussion Starter · #1 ·
Hi, first post here so be kind 馃榿.
I have owned the 06 T30 XTrail for 10 yrs (ish) and up to now have managed most repairs myself.
The front subframe cracked on the front wishbone joint having rusted.
So I have decided to take the subframe off, I have cracked open most of the bolts but two (same on each side) directly behind the strut.(see image)
I have a long bar, and have also tried an impact gun but they are not moving.
I am reluctant to use heat as i think there is a rubber bush in there.
I am not entirely sure how this joint works without seeng the inside, and also unsure about how easy it will be to source parts IF I have to either grind it off OR use a flame and knacker the bush.

Any advice gratefully accepted馃憤馃憤
 

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Discussion Starter · #3 ·
Thanks for the reply.
Very good tip , for the record this is exactly what i did today - it was very tight but eventually cracked on tightening as there is some way to go with the bush.
The other side is another story - but will persevere.
 

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Hi, first post here so be kind 馃榿.
I have owned the 06 T30 XTrail for 10 yrs (ish) and up to now have managed most repairs myself.
The front subframe cracked on the front wishbone joint having rusted.
So I have decided to take the subframe off, I have cracked open most of the bolts but two (same on each side) directly behind the strut.(see image)
I have a long bar, and have also tried an impact gun but they are not moving.
I am reluctant to use heat as i think there is a rubber bush in there.
I am not entirely sure how this joint works without seeng the inside, and also unsure about how easy it will be to source parts IF I have to either grind it off OR use a flame and knacker the bush.

Any advice gratefully accepted馃憤馃憤
There is a very simple rule in this type of situation, nuts are replaceable, but if you damage or break off that particular bolt (or the other three like it) you are in serious trouble. There is no point in trying to get cute or just hope the nut will eventually loosen somehow maybe with enough penetrating oil and a little more force. Sacrifice the nut. In the climate and conditions where I live, namely Nova Scotia, seized nuts and bolts even on cars not that old are a fact of life. The location of the seized nut (as I can see in the photo) gives you several options to cut the nut to remove it. One possibility is to cut off one or two sides of the nut, being very careful not to get down to the bolt threads. You could use a small angle grinder with a thin cutoff wheel and carefully slice off at least one side of the nut, and of course not too close to the bolt. In most cases just removing material from the nut will weaken it and it may come off with a regular socket, or even better, one of the special sockets designed for use on damaged nuts (or bolts). Rather than an angle grinder I would use my electric cut-off grinder (smaller than an angle grinder and that takes fairly thin small diameter disks). However in your case my preference would be using one of my air-powered die grinders, and I have a good collection of carbide cutters for them. With a die grinder and a small cutter you can make a groove in two flats of the nuts (not down to the threads of course) and then you may find the nut has weakened and can be removed with large pliers, etc. If it doesn't you can take a small cold chisel and position the chisel at an angle in one of the groves of the nut, in the direction the nut would unscrew, (so not pointing directly at the bolt) and give it a hit. In that situation I use an air chisel, positioned similarly to the cold chisel, and usually one brief snap of the air chisel will split the nut and it will probably fall off.
Of course even with all 4 nuts removed there is a good chance that the bolt is seized on the inner sleeve of the bushing that really holds the frame on. However, you will be replacing the old piece with a new one so you don't care how much you butcher the one on the vehicle to get it off. You may have to slice each of the 4 housings around the support bushings to get the old frame off, then chew off the rubber bushings to get down to any of the seized inner sleeves. At that point you will spray whatever anti-seize liquid you've got, at the top of the sleeve, let it work then try pliers or something similar to try to twist the sleeve around the bolt to free it. Once you can do that the sleeve can be removed. In the worst case you will have to carefully grind away a small region one side of the seized sleeve, also being careful not to damage the bolt. The last thing you really should do before installing the replacement frame is to use the proper die to clean up the threads on the 4 bolts.
I know some oxyacetylene enthusiasts will recommend cutting the nut off that way but I don't have that set up, don't want it. Using acetylene is tricky in order to avoid damaging components around the target, especially in your situation, and also setting stuff on fire. As well, you'd better be sure you have a fire extinguisher handy and live near a fire station if you choose that method.
 

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There is a very simple rule in this type of situation, nuts are replaceable, but if you damage or break off that particular bolt (or the other three like it) you are in serious trouble. There is no point in trying to get cute or just hope the nut will eventually loosen somehow maybe with enough penetrating oil and a little more force. Sacrifice the nut. In the climate and conditions where I live, namely Nova Scotia, seized nuts and bolts even on cars not that old are a fact of life. The location of the seized nut (as I can see in the photo) gives you several options to cut the nut to remove it. One possibility is to cut off one or two sides of the nut, being very careful not to get down to the bolt threads. You could use a small angle grinder with a thin cutoff wheel and carefully slice off at least one side of the nut, and of course not too close to the bolt. In most cases just removing material from the nut will weaken it and it may come off with a regular socket, or even better, one of the special sockets designed for use on damaged nuts (or bolts). Rather than an angle grinder I would use my electric cut-off grinder (smaller than an angle grinder and that takes fairly thin small diameter disks). However in your case my preference would be using one of my air-powered die grinders, and I have a good collection of carbide cutters for them. With a die grinder and a small cutter you can make a groove in two flats of the nuts (not down to the threads of course) and then you may find the nut has weakened and can be removed with large pliers, etc. If it doesn't you can take a small cold chisel and position the chisel at an angle in one of the groves of the nut, in the direction the nut would unscrew, (so not pointing directly at the bolt) and give it a hit. In that situation I use an air chisel, positioned similarly to the cold chisel, and usually one brief snap of the air chisel will split the nut and it will probably fall off.
Of course even with all 4 nuts removed there is a good chance that the bolt is seized on the inner sleeve of the bushing that really holds the frame on. However, you will be replacing the old piece with a new one so you don't care how much you butcher the one on the vehicle to get it off. You may have to slice each of the 4 housings around the support bushings to get the old frame off, then chew off the rubber bushings to get down to any of the seized inner sleeves. At that point you will spray whatever anti-seize liquid you've got, at the top of the sleeve, let it work then try pliers or something similar to try to twist the sleeve around the bolt to free it. Once you can do that the sleeve can be removed. In the worst case you will have to carefully grind away a small region one side of the seized sleeve, also being careful not to damage the bolt. The last thing you really should do before installing the replacement frame is to use the proper die to clean up the threads on the 4 bolts.
I know some oxyacetylene enthusiasts will recommend cutting the nut off that way but I don't have that set up, don't want it. Using acetylene is tricky in order to avoid damaging components around the target, especially in your situation, and also setting stuff on fire. As well, you'd better be sure you have a fire extinguisher handy and live near a fire station if you choose that method.
Hey, how long and do you have a vid or how to for removing the Subframe? Thanks so much.
 

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Hey, how long and do you have a vid or how to for removing the Subframe? Thanks so much.
Well you are asking about removing the front subframe and I have lots of experience working on (replacing) the rear suspension member ("subframe") but I have never worked on the front specifically. However there are clearly similarities between the front and rear and the problem you are having with one of the support studs is the same problem that I had with the rear suspension member equivalents. In your original post you were fighting with a seized nut. So did you ever get the nut off? If the nut is off I assume you've discovered that one or more of the studs that drop down from above is seized in the bushing(s), technically in the metal sleeve on the inside of the bushing.
I am attaching a few files. The first 3 are the appropriate pages on the front suspension member taken from the service manual. The first and second pages include a schematic and the third is the service manual's very short instructions for removing the front assembly. I'm adding a second schematic of the front suspension member plus a page from the Transfer Assembly section of the manual that shows the 'Center member" that you have to remove first before removing the front suspension member. Finally there is a photo of (one of the 4) actual studs that holds the suspension member on. That last photo is of a rear part but the front are identical I'm sure.
If you have all the nuts off you have to try to get some penetrating oil or that type of product in the bushing, both from the top but as you can see from the photo you can also squirt liquid up from below. What I found that was really effective at getting the suspension member off the four studs was an air chisel with a flat ended bit. After treating the four bushings and giving that a day or so to soak in I took the air chisel, positioned the bit on the upper part of the bushing housing, with the tool pointing slightly download, and gave it a several seconds blast. Once one stub had clearly just started to let go I went to another bushing and repeated that, so going around again and again, driving the bushings down the bolt gradually.
Before you can remove the front suspension member you do have to disconnect the center member, the control arms and a few other items as described in the manual.
 

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