To drop subframe or to not on an AUTO...

[winstonk]

I know this has been discussed a million times. But there is not much info on not doing the reinforcements on a non abused 0 rust car AUTO. I dont believe iv seen any AUTOs with torn sub frame sheet metal.

Long story short i have all the parts for my suspension build. All engine maintenance is done (water pump, icv, ccv, vacuum lines, ect.)

Im ready to bring this thing over to my buddies lift to and have at it. But im starting to wonder if its really necessary to drop the sub frame so i can have someone weld in the reinforcement plates.

Its going to be a non engine modded DD with BC racing BR coil overs. I went with the softer 6k/8k spring rates.

I see alot of people saying there sub frame bushings where not worn at all. Some say reinforcement plates are not necessary. I have 130k on my grandma driven AUTO 328i.

[ChuckDizzle]

I know this has been discussed a million times. But there is not much info on not doing the reinforcements on a non abused 0 rust car AUTO. I dont believe iv seen any AUTOs with torn sub frame sheet metal.

Long story short i have all the parts for my suspension build. All engine maintenance is done (water pump, icv, ccv, vacuum lines, ect.)

Im ready to bring this thing over to my buddies lift to and have at it. But im starting to wonder if its really necessary to drop the sub frame so i can have someone weld in the reinforcement plates.

Its going to be a non engine modded DD with BC racing BR coil overs. I went with the softer 6k/8k spring rates.

I see alot of people saying there sub frame bushings where not worn at all. Some say reinforcement plates are not necessary. I have 130k on my grandma driven AUTO 328i.

With a coilover setup, I'd recommend reinforcing the shock towers with the reinforcement plates. With stock suspension I haven't seen any mount failures, but I've seen several instances where the shock (aftermarket) came through the mount or the sheetmetal around the mount tears.
As for reinforcing the subframe, I'd say it's really up to you but its not a bad thing since it's one of those "while I'm in there jobs" when you redo the suspension. Some though might think it's overkill.

[winstonk]

I already have the shock tower reinforcements.

Im more interested in the sub frame reinforcements. Sense i have an AUTO im hoping to not drop the sub frame and just replace the other bushings. I have the koch tool for my trailing arms already.

Basically if its a grandma driven AUTO, garage kept 0 rust, Florida car. Is it necessary to do the sub frame bushings/reinforcements without kicking myself in the ass when 200k comes around and i start hearing clunking cause i tore the sheet metal.... I just keep seeing posts of people saying there sub frame bushings look brand new at 130k+

Just looking for some verification :) I understand this has been beaten to death but like i said not much AUTO info. Everyone has a manual.

[ChuckDizzle]

I already have the shock tower reinforcements.

Im more interested in the sub frame reinforcements. Sense i have an AUTO im hoping to not drop the sub frame and just replace the other bushings. I have the koch tool for my trailing arms already.

Since you're leaving the car primarily stock and don't plan on track time, I'd say the subframe reinforcements are overkill. Now, if you had an early build date E46, I'd say its a necessity :shifty

[winstonk]

Thanks for verifying that for me chuck!

I'll be sure to hunt you down if my sub frame tears before my AUTO transmission goes lol :)

[ChuckDizzle]

Thanks for verifying that for me chuck!

I'll be sure to hunt you down if my sub frame tears before my AUTO transmission goes lol :)

I'll personally guarantee that your automatic transmission will blow before the subframe does ;)

[UnderCoverGuy11]

I'll personally guarantee that your automatic transmission will blow before the subframe does ;)

+1

[winstonk]

Sweet! I knew i was going above and beyond with this build. Now i can just put her on jack stands in my driveway and take my time :) I'll take that money i was going to spend on a mobile wielder and rebuild my vanos.

Im also putting less stress on my sub frame with an auto transmission, correct?

So unless someone can convince me to replace my sub frame bushings. I read they can be considered lifetime bushings on DD? I'll sell my AGK black sub frame bushings and reinforcement plates.

[ChuckDizzle]

Sweet! I knew i was going above and beyond with this build. Now i can just put her on jack stands in my driveway and take my time :) I'll take that money i was going to spend on a mobile wielder and rebuild my vanos.

Im also putting less stress on my sub frame with an auto transmission, correct?

So unless someone can convince me to replace my sub frame bushings. I read they can be considered lifetime bushings on DD? I'll sell my AGK black sub frame bushings and reinforcement plates.

I will not convince you that the subframe bushings are lifetime. AKG makes great bushings, I highly recommend them.

[r33p04s]

put in new subframe bushings...skip the plates

[flyfishvt]

Subframe bushings are a bit of a pain to get out but easy to install. RTAB's are fairly easy to get out but the stock ones (non poly) are a pain to install. I won['t even talk about all 4 control arm bushings. I had a shop install my lower/inner bushings. Best $60 I spent. I did the others with some homemade bushing presses. If you have access to a hydraulic shop press or the actual bushing remove/install tool its a snap to do all of them.

I cant say whether or not ot install the plates but my car is 150k and I live in high salt area and I did not install them. The car looked fine once I had everything out.

If you're doing all of your rear bushings you might get some good info from this

http://forums.bimmerforums.com/forum/showthread.php?t=1848357