attritorman

Hello Everyone,

I have a 2006 TL with 56,000 miles. I just returned from my dealership with some bad news after some routine maintenance. I just found out that the front compliance bushings had worn out causing the lower control arms to sit directly on the subframe. I must have driven around with this condition for some time because the subframe now has some wear damage around the bolts on both sides (see attached kind of blurry pic). I need some advice/help/feedback from the great members of this forum.

1. Can the subframe be welded/repaired or do I not want to even venture down this path?

2. If I should replace the subframe, where is the best place to purchase one? The dealership says a new one runs almost $4K but they can locate a used one for $1K.

3. If I replace the subframe and the compliance bushings, is there anything else related I should go ahead and have replaced so I have less to worry about down the road?

I love my TL and would love to be able to drive it several more years. The thought of putting a few thousand dollars into this has me wondering if I should bite the bullet and do it or move on and start looking for another vehicle. Any thoughts/comments is greatly appreciated.

Thanks,
Attritorman

Houston

How the heck does the sub-frame have that much damage with only 56k on it?? My TL has about 180k on it, the frame gets hit quite often because of the drop, the bushings are original and have been torn forever, and I place my jack stands on that exact spot, yet my frame still looks decent...

Welding the frame should be ok, but if you really want to replace it, look for a decent one at a salvage yard and buy new bushings. Should still be cheaper than a grand. Although, you will still have to pay to get it installed and have the bushings replaced.

Honestly, if it was me and money was tight, which it always is.. , I'd have it welded and just replace the bushings.

mzilvar

iTrader: (3)

Make sure whoever welds it knows the subframe is aluminum, I'm sure their process for welding is going to be different.

I don't know much about welding though.

dcmodels

I own an RDX instead of an TL, and the RDX front sub-frame is steel. So forgive me if my comments are not correct - if the TL subframe is aluminum I would *not* have it welded, but replaced with a used one - and examine carefully the used one - if dealer buys and replaces it they will be carefull simply because of the liability.

Now, your picture is not perhaps clear enough but if the subframe is solid, that is not enough damage to matter, speaking as an engineer. But brush paint the damaged area, then spray with 3M rustproof p/n 08892 18oz or 3M undercoating p/n 08883 19oz to prevent corrosion. The OEM part will have some sort of coating to prevent corrosion. Bare aluminum will corrode to the point of failure, and not be obvious.

But as I say, I cannot tell from your pic if its solid or aluminum tubes. If tubes then should be replaced. JMO

mzilvar

iTrader: (3)

Here you go:

HYDROFORMED ALUMINUM-ALLOY SUBFRAME
To reduce mass and improve handling agility, the 2004 TL uses an all aluminum-alloy front subframe that carries the engine, transmission and lower suspension links.

The U-shaped subframe cradle is hydroformed. In this process, a single aluminum-alloy tube is inserted into an immensely strong die, which is locked closed before the tube is pressurized with water. The resulting component is lighter and stronger than a multi-piece component would be. The hydroformed cradle is then attached to aluminum-alloy corner brackets to form the complete subframe.

Compared to the traditional steel subframe on the 2003 TL, the aluminum-alloy TL subframe weighs 36 percent (about 23 pounds) less. Besides its lighter weight, the new subframe has increased bending rigidity, which reduces noise experienced in the passenger cabin, particularly as the engine is starting.

Taken from here:

http://www.honda.com/newsandviews/ar...spx?id=1400-en

I also thought aluminum oxidizes so rapidly on the outside that it almost instantly forms Aluminum oxide on the exterior of plain aluminum and then is too porous for it to penetrate any further into the aluminum? A lot consider the aluminum oxide that forms to be a protective layer that prevents further corrosion. Never seen anything aluminum corrode into two pieces.

I do know a lot of people say it's not possible to weld aluminum, but I can't really speak to that I have no experience welding.

dcmodels

In theory sure, depends upon the alloy and the conditions to which it is exposed, as to how much it will corrode. 6061 is mild and will not really corrode (oxidize), while 7075 (and similar alloys) is used to build airplanes, is much stronger and less maleable (than 6061), and requires some corrosion protection, esp when used in an airplane. Those jumbo jets in which you ride are regularly inspected just to make sure the wing is not about to fall off, from corrosion. There are also problems with electrolysis caused corrosion of both aluminum and steel.

Most aluminum can be welded (heli-arc), but that does not mean that the result will be as strong as the original part - again, depends upon the alloy and the conditions under which the *welding* is done. In any case, even welding the special alloy-steels used in modern cars requires some considerable care, and is not something generally recommended.

dcmodels

Quote:

Originally Posted by mzilvar

... Never seen anything aluminum corrode into two pieces. ...

Aluminum wheels are painted, both outside and inside the rim (inside the tire area) - for a reason - corrosion. The particular alloy of which most car wheels are made, are especially prone to corrosion, to the point that the (unpainted) aluminum becomes like old moldy cheese.

Tire dealerships are well aware of this problem. That is why the current procedure is to buff the backs of the wheel hub, to remove the corrosion, using an air-wrench w/ 3M pad attachment. That part of the wheel is either not painted to begin with, or the paint simply comes off the first time the wheel is removed.

I myself apply a very thin layer of aluminum type anti-seize, to the wheel hub and the disk brake rotor hub, whenever I rotate tires, just to prevent the wheel from rusting into place on the rotor hub.
===================

Also, the inside of the wheel rim, where the tire bead seals, is another place where corrosion is a real problem, because of moisture inside the tire (moisture from the air inside the tire).

In the eastern USA it is not at all unusual to have to replace wheels after 5-6 years. It partly depends upon how often the tires are *busted* from the wheels. One reason why I don’t like to have my tires rebalanced unless necessary. Here in the mountain states, my Chevy dealer has seen some wheels after 10 years or even a shorter period that require replacement.

Again, current practice in tire shops is that they are supposed to use a tire lubricant when seating the tire bead, that also contains a special anti-corrosion inhibitor. And I have seen them use an air-wrench with a wire-brush to remove the corrosion on the inside tire rim/ bead area, which just causes more and faster corrosion, as that obviously removes any existing paint.

So yes, aluminum certainly does corrode, to the point of failure.

mzilvar

iTrader: (3)

Cool, learn something new all the time haha

I knew about galvanic corrosion though.

Sounds like a new subframe is the safest bet for the OP, that sucks, thats going to be expensive to transplant everything over and then the AC system is going to need to be discharged in the process which means a new dryer and condenser? Not sure what the best practice for that is, but I know at least a new dryer.

YeuEmMaiMai

replace sub-frame should be a few hundred $$

EDIT: Fudge that $500+

attritorman

Thanks for all the feedback thus far guys. I am pretty disappointed with my dealership (not sure if it is justified but I feel it is as I take my TL there for all regular maintenance) for not letting me know about the condition of the compliance bushings before they failed. Is this something that gets inspected as part of any of the maintenance services?

At any rate, they quoted me $1800 for a used subframe installed. Then add another $400 for new compliance bushings (installed).

The rest of the subframe is in very good condition. The only part that is damaged are the semicircles around the bolts on both sides. I don't think it is in immediate threat of catastrophic failure or my dealer wouldn't have let me drive off...or at least I like to think so. I am going to take my car to another trustworthy mechanic next week to have him take a look and give me his opinion. We do also have a local weld shop that I will be going to for an opinion on the weld repair.

I'll keep you posted and thanks again to everyone for their input.

nfnsquared

Adding $400 to install the bushings is a total scam...

Are you sure that price isn't for installing 2 new lower control arms with bushings?

paperboy42190

iTrader: (7)

$400 to change new bushings isn't too bad, that's a pretty standard stealership price. But if they alrdy have the subframe off it'd barely take them any more work to do the bushings.

YeuEmMaiMai

that part new is over $3200 WTF?

paperboy42190

iTrader: (7)

^dont be so surprised. there are some things in the car that would surprise a lot of ppl on how much they cost.

for example the dvd drive is over 2k, backup camera is over 1k, etc

attritorman

Do you guys have recommendations for reputable places to buy parts? I am looking for the subframe, compliance bushings, sway bar links, brake calipers, etc.

Thanks,
attritorman