smartypants

Off all the most simplest and stupidest jobs, changing out the license plate surround has got to be right up there along with checking tire pressure. Unfortunately, it took me over three hours to do it and I probably did more damage to the car than if I had just left it alone.

Removing the rear license plate screws caused the "u-clips" the break in two pieces and spin around without ever coming out. after trying to come up through the bottom, I thought if I could remove the plastic fasteners in the trunk threshold, might allow me to gain access to behind the top of the bumper and get some vice grips on the clips. When I took off the fasteners, a great chunk of metal fell out and suddenly all the receiving holes for the fasteners under the plastic threshold were gone. Whatever is underneath has seriously rusted out. I will need to take off the bumper cover and see what's there. I'm hoping it's the top of the bumper I-beam as these can be replaced, but I can't seem to find a picture or drawing of what's located in this spot.

With this latest issue, it seems my old car (which I bought brand new in 1999) is approaching it's final days and I need top face the fact that it's time to replace it.

If anyone has had this section of a TL apart, I'd really like to know what's underneath.

fsttyms1

Are you talking about #21, the upper bumper beam

smartypants

I'm not quite sure because I can't seem to find a picture of it assembled. Even with your diagram, where does 21 fit in relation to 20 ? I have a sneaky hunch my issue is with 20....a piece not easily replaced. I think 21 sits out front of 20.

Thanks for the response. Always nice to get a response from our resident "brain trust". Have you ever had this part exposed, rear bumper off ?

3.2TLc

Yeah, it appears that the upper beam sits on top of the main bumper support beam. The holes for the bumper cover's hooks are probably located on that upper section. My guess is that once the bumper cover is off, you'll be able to either replace the inner support beam or the part which fell off. Perhaps fabricating a bracket and then attach it to the beam would be possible ?

How many miles on the TL ?....and how is the tranny ? Once you're over 200k, the hard work is usually behind ya, IMO. Keep it for a winter beater back-up to the new car !

smartypants

Thanks 3.2 and yes, once I get the bumper off I'll be able to see the extent of the damage. My first though is to find a welding shop and get them to "graft" a new section in.

I'm sitting at around 105K miles, which I know is relatively low for these cars. After the trans re-build and timing belt last year, the engine and trans are running fine. However, I'm starting to get age related problems like rust. I also have to replace both mufflers (which I have already purchased) and I just found that the rear brake backing plates are rusted out.

I know I'm in the old car "cycle of money" and the scrap yard is starting to look like a better and better option.


And so it goes.......

victus1

Smarty, spraying the car with oil at Crown rust control annually or even every other year works wonders at stopping rust. Mine is still bleeding some oil from the interior panels when I had it sprayed 2 years ago. Will do it again in the fall.

smartypants

Thanks for the reply victus.

Unfortunately, I think its too late for rust proofing. I think the rust has now progressed to a point where any preventative actions will not yield much benefit.

3.2TLc

Hey Smarty, it's sad that rust is the factor which has dealt your present scenario of giving up on the TL.

Consider a "southern states" body donor to utilize your drivetrain and other valuable components which undoubtedly have lot's of life left in them. Run your 105k car until it's undercarriage is unsafe. Another solid rustfree TL should be easy and cheap to locate, especially with tranny issues and higher mileage. Swap your newer low mileage parts to the donor and ya got a bargain.

smartypants

lol !!!

3.2....Unfortunately, I don't have the equipment, facilities or the time for an effort of that magnitude.

I'll leave that sort of project for a more adventurous sole.....

I'm continuing to look at ways to fix this, but if its rusted like this in this one place, other spots are not far behind....

smartypants

So, I finally dropped the rear bumper cover and here's what I found.

I suspect there's more of these situations than we might think as I found this by pure accident, no symptoms what so ever. Pics below.

You can check this by taking off the plastic fasteners on the trunk threshold and seeing if the metal underneath is still solid. You might even be able to move the bumper back enough to get a look-see at the deck plate.

I'll need to change the upper deck piece and the bumper beam.

smarty...

smartypants

After a lot of planning, running around and just plain elbow grease, the bumper beam situation is resolved.

I ended up going to a wreckers and got an upper and lower rear bumper bean. I believe they were from a 2003 but fit fine on my 1999. Took the pieces to an auto body place had them sandblasted to remove all the paint and surface rust, yes these were also beginning to rust. Repainted them both (using a brush) with commercial-grade auto frame paint.

Interestingly, when I removed the old lower bumper beam, I could put my hand through the gaping rust holes underneath. If anything had hit me from behind, it would have been as much use as a box of soda crackers.

Also, the upper beam is spot welded to the body and entailed drilling out the spot welds and using a sharp chisel to break the rest of the welds. The one on the car was easy to remove as most of it had simply disintegrated ! Stainless steel #10 screws to re-attach the upper beam and four bolts to re-mount the lower bumper beam.


I would encourage everyone with an older TL to check the bumper beams as a high speed rear end collision would be significantly more dangerous and destructive if this critical piece is rusted to the point mine was.

To check it, simple crawl under the rear of the car and shine a light up in the gap between the fuel tank and the bumper cover and you should see the bottom of the lower bumper beam.

Sorry no pics as my cell had no battery left when I went to take some shots…..

smarty

3.2TLc

This is simply amazing informative shit for safety mandated standards imposed upon car manufacturers.

Sad, but true !!! do they really care ?

The internal support beams should withstand minimum Gov't regulated "MPH" impact protection. Ha, hah.... looks good on the outside thanks to the plastic bumpers. Gotta love the beauraucity and it's pretend mentality. Looks good on the outside, But....WTF !!!! Outa warranty, outa mind. Check your vehicle today, as your life may depend upon it tommorrow. Geeesis, where's the commitment to our safety ????

Thanks for unveiling the truth !!! I once had a Dodge Caravan, similar scenario....wtf, family van and then even the rear transverse support beam rusted and broke.

fsttyms1

The main point of the bumper beam is for low speed crashes (the govt standard 2.5mph stuff like backing into poles etc..) the actual portion of the crash protection comes from the unibody structure, not the bumper itself.

fsttyms1

The bumpers arent designed to protect you more in high speed impacts. They are designed mostly for the low speed impacts and for some of the offset impacts to initially distribute the force a little more and to support the plastic bumper itself. All of the safety for the occupants from large impacts/crashes comes from the vehicles structure itself and the predetermined crumple zones to absorb the impact (you can see them on the front frame rails when you open the hood)

fsttyms1

This is a bumper from a new F150/raptor, the Gray part is metal, the black is plastic. The plastic connects the 2 sides and continues to the top. Almost Zero metal structure. And what is there is pretty thin. Bumpers arent designed for large impacts.








Yep, that is all there is too it.

3.2TLc

Yeah, thanks for the clarification. Makes totally good engineering sense.
The bumpers and their support are only for minor bumps as ya said, but the frame "impact" crumple zones can also be compromised by rust, IMO.

fsttyms1

But again, those would really only effect the bumper impacts. The main strength and crumple zones of a car are the body panels and the inner panels, most of which you dont see. The mounting areas of the bumper beams and bumpers if rusted wont effect overall safety. Now if you see rust further on inner panels, rockers rusted out etc.. then there would be more concern about safety and integrity of the car.

smartypants

I see the point and agree the high speed impact is "managed" by crumple zones. However, the rear bumber beam on the TL is a considerable piece of hardware and is clearly designed to mitigate more than just a low speed crash. This is all goodness until you see what I saw and wonder why after clearly over engineering this part, they chose to use such a rust prone metal. Even a simple rust preventive coating would have prevented this all from happening.

Fortunately, removal is just four nuts and it slides right off making the beam replacement a very simple task indeed. However, the upper beam (also prone to rust) is a significantly more complicated matter.


smarty

Gabru678

iTrader: (1)

Well in order to prevent rust what can we do?
Is there a frame spray that is available? Or some sort of coating that we could use?

Skirmich

^^Just sand, prep and paint the rusty areas with primer beneath the Brake lights.. Primer will stick like mud in to the metal and will protect it.
No need to paint since that part is covered with bumper.

To OP: HOLY MOTHER OF RUST!

fsttyms1

Most bumper beams are a considerable piece of metal. But regardless of how big they are, the main purpose is for low speed impacts. Especially in the center usually with a pole to keep the damage away from the rest of the car. You might be surprised at how easily what you think is a honkin big piece of metal like that will bend.