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How do you reinforce the front sub frame?


josh72ooh2
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I was looking through my 10 year old records from my old 2002 and saw that i had a place in the east bay reinforce my sub frame.

How do you go about doing this?

I assume it has something to do with the motor mounts?

Does the engine have to be pulled or lifted?

Is there anybody in Los Angeles who can do the job?

My engine/tranny has some serious wiggle and curing it is on my list... along with replacing the tranny and engine mounts.

-josh

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flexibly, so expect some movement--probably more than you're used to seeing in other cars. That being said...

I'd check both motor mount brackets. The driver's side one--the ear that sticks up from the subframe near the steering box--is the one that historically fractures and should be carefully checked. If it's OK, there's a later style motor mount that's somewhat stiffer to replace the round one.

On the pax side, check both the rubber mount itself as well as the bracket. The mount can be broken and it's hard to tell as the weight of the engine will make it look as if it's still in one piece when it's broken. Mine had been broken for a long time before we discovered it after pulling the engine.

And the bracket that bolts to the subframe: early ones were a single folded over piece of heavy steel; they stress cracked and will eventually collapse (mine did on my '69). Later brackets (not sure when they were introduced but probably sometime in 1970 or 71) are welded up from several pieces and have a bracket to hold even a broken mount in place--something the early brackets don't have.

If you don't know when your mounts were replaced, do 'em both, and check both mounting brackets for cracking. And unless it's a track car, I'd use rubber mounts; otherwise you're gonna get a lot of vibration transmitted to the car's body.

cheers

mike

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Just to add to what else has been said so far: You'll have to either pull the engine or drop the subframe off the bottom of the car to weld in the reinforcement on the driver's side mount riser.

Here's a pic of how I had mine done with 1/8 or 3/16 plate steel. What ever thickness it takes to bring the nut flush with the end of the bolt on the mount. The steering box was also removed for this.

post-71-13667631857445_thumb.jpg

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