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nbristow01

Cracked push rod at the rear subframe bushing

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I leave Thursday for Eureka Springs with the BMWCCA fall tour. So inspecting my car before I go (mine is a 1974 2002)The rear end has felt a bit squirely for the last few days so I started looking. I see by right side rear pushrod has a crack..see pic. I am taking it tomorrow to get welded but would like to know why it may have cracked. The crack is not all the way across, only as long as seen in the photo. I have never replaced the rear subframe bushings on the car and I have put 100K on the car so far. So most likely 200k plus on these subframe bushings. I am not sure if this is the source of the loose feeling I am having at the rear of the car.

I have new subframe bushings so I guess I might as well install them before I go. Has Bilstien HDs on back, IE sway bar. Old a arm bushings

I appreciate any opinions

Also I have looked for a good post for a step by step replacement. I found a bunch with Poly installs but none with stock. If you know of a good post can you please send me the link

post-17424-13667665581866_thumb.jpg

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They are effectively limiting straps for side to side subframe movement. Its understandable to see them buckle and crack that way, especially if your racing/aggressively driving on old worn out subframe bushing.

As for replacement tutorials, any of the ones going over the subframe inserts in conjunction with mount replacement would suffice as the only difference is your just putting not putting the insert in the bushing.

A long term solution might be to have your welder add some extra metal reinforcement on the straps. On the shop race cars we make a piece utilizing a heim joint and steel DOM tubing, been debating whether or not to put it into production.

IMG_4665.jpg

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They are effectively limiting straps for side to side subframe movement. Its understandable to see them buckle and crack that way, especially if your racing/aggressively driving on old worn out subframe bushing.

As for replacement tutorials, any of the ones going over the subframe inserts in conjunction with mount replacement would suffice as the only difference is your just putting not putting the insert in the bushing.

A long term solution might be to have your welder add some extra metal reinforcement on the straps. On the shop race cars we make a piece utilizing a heim joint and steel DOM tubing, been debating whether or not to put it into production.

IMG_4665.jpg

Thats a nice looking part. I would buy them because I will now have a welded crapppooooo one on my car...What would they cost?

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If you are still running the original trailing arm bushings, I will wager that is where your slop will be found.

Earl

74 02Lux

02 M Roadster

72 Volvo 1800ES

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If you are still running the original trailing arm bushings, I will wager that is where your slop will be found.

Earl

74 02Lux

02 M Roadster

72 Volvo 1800ES

I bet you are right.

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Guest Anonymous
I leave Thursday for Eureka Springs with the BMWCCA fall tour. So inspecting my car before I go (mine is a 1974 2002)The rear end has felt a bit squirely for the last few days so I started looking. I see by right side rear pushrod has a crack..see pic. I am taking it tomorrow to get welded but would like to know why it may have cracked. The crack is not all the way across, only as long as seen in the photo. I have never replaced the rear subframe bushings on the car and I have put 100K on the car so far. So most likely 200k plus on these subframe bushings. I am not sure if this is the source of the loose feeling I am having at the rear of the car.

I have new subframe bushings so I guess I might as well install them before I go. Has Bilstien HDs on back, IE sway bar. Old a arm bushings

I appreciate any opinions

Also I have looked for a good post for a step by step replacement. I found a bunch with Poly installs but none with stock. If you know of a good post can you please send me the link

Pushrod??

Repair and replacement is covered in factory manual and Haynes. Cracked link /tension strap is easily replaced with used part.

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I leave Thursday for Eureka Springs with the BMWCCA fall tour. So inspecting my car before I go (mine is a 1974 2002)The rear end has felt a bit squirely for the last few days so I started looking. I see by right side rear pushrod has a crack..see pic. I am taking it tomorrow to get welded but would like to know why it may have cracked. The crack is not all the way across, only as long as seen in the photo. I have never replaced the rear subframe bushings on the car and I have put 100K on the car so far. So most likely 200k plus on these subframe bushings. I am not sure if this is the source of the loose feeling I am having at the rear of the car.

I have new subframe bushings so I guess I might as well install them before I go. Has Bilstien HDs on back, IE sway bar. Old a arm bushings

I appreciate any opinions

Also I have looked for a good post for a step by step replacement. I found a bunch with Poly installs but none with stock. If you know of a good post can you please send me the link

Pushrod??

Repair and replacement is covered in factory manual and Haynes. Cracked link /tension strap is easily replaced with used part.

RealOEM calls it a pushrod...see attached pic

12 PUSH ROD 2 33333428125 $35.45

I do not see where it is called a link/tension strap as you stated. Is that the correct name for this part?

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I do not see where it is called a link/tension strap as you stated. Is that the correct name for this part?

Yes, I'm guess the BMW English translator did not have their cup of coffee yet when this page went across their desk.

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Guest Anonymous

I am a coward so I make useless comments on posts without logging in.

I also do not understand what FAQ stands for

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Just looking at the first picture I believe the push rod/ strap has been used as a lifting point or abused some other way. There is suposed to be a slight bend right at the attachment point at the body and again right at the crossmember mount, the rod/strap should be STRAIGHT between those 2 points. This abuse/ damage is very common and very easy to replace (if someone has not totaly trashed the threads on the end of the bolt through the silent block on the crossmember, in which case getting the nut off will be a royal pain.

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Nick -

What does the inside of the large subframe bushing look like? Look closely at the rubber to see if it is cracked or separated from the metal part. Jack up the car at the subframe, put it on stands and also inspect the trailing arm bushings.

Use a pry bar to see if the bushings are really sloppy.

IMG_8060.jpg

Here are two trailing arm bushings I just removed that were in good shape.

IMG_7868.jpg

It looks as if the car was jacked up at the incorrect points.

Jim

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What? No, that's just the 'engineering kluge strap' that turns the single shear

rear subframe bolt into a double shear joint.

It's remarkably effective for being such a bodge.

And unless your rear subframe attach point's a rusty mess,

I'm also going to guess it's from a jack slipping off the bolt.

Never had trouble with those that wasn't caused by a jack.

Not a big deal, UNLESS the bolt's loose. Then it's worth finding the root cause.

t

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Factory Parts Book translates it as a Thrust Rod. FWIW

Pushrod??

Repair and replacement is covered in factory manual and Haynes. Cracked link /tension strap is easily replaced with used part.

RealOEM calls it a pushrod...see attached pic

12 PUSH ROD 2 33333428125 $35.45

I do not see where it is called a link/tension strap as you stated. Is that the correct name for this part?

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Factory Parts Book translates it as a Thrust Rod. FWIW

Pushrod??

Repair and replacement is covered in factory manual and Haynes. Cracked link /tension strap is easily replaced with used part.

RealOEM calls it a pushrod...see attached pic

12 PUSH ROD 2 33333428125 $35.45

I do not see where it is called a link/tension strap as you stated. Is that the correct name for this part?

Thanks Les for the correct nomenclature of that part. I had my Thrust Rod welded this AM. Are you back in the US? A bunch of us got together with John (AKA HARV on FAQ) and we talked about where you may be now

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