Most infuriating thing I've encountered on the TM3 yet: Removing the rear diffuser

[Dolemite]

Just a heads-up for everyone who might have to do this. Long story short, I had to remove my rear diffuser (1135410-00-A).

The bolts holding it in place are supposed to be tightened to 3 ft-lbs. For gadget freaks still in the "how dose tire work?" phase, that means a toddler could potentially shred the bolt.

I don't know wtf they did at the factory, but it took me 45+ minutes to get these things out using a 3/8" ratchet in conjunction with vice grips. It seems like they might've fastened it down before the galvanization had completely cured? I'm referring specifically to the ones that go through the middle:

They go through these bosses that are attached to flimsy sheet metal mounts welded to the bottom of the sub-trunk. Despite my best efforts, they sheared off, but luckily no damage was done to the mounts which bend like an aluminum can:

I coated the mounts w/ rust-proof paint & replaced the bosses with these washers I bought from NAPA which have a nice plastic coating to prevent gouging into the metal:

God damn it Tesla.

 

[Perscitus]

I feel your pain @Dolemite. We were just talking about this in another thread (forget the topic) maybe a week or two ago.

The biggest pain is removing or reinstalling the deep recessed screws that together with pushpins hold the thin lip (what Tesla calls the diffuser and is anything but on the Model 3) thats left behind when you remove this rear splash shield.

Whoever thought that was a good design decision fits the stereotype of an automotive industry subassembly engineer.

 

[MasterC17]

Tesla started adding loctite to these bolts (same as the ones in the front aero shield and mid aero shield) in 2019, presumably to address the "rear bumper flying off" concerns (which IMO really was just bolts that hadn't been properly torqued to begin with). Unfortunately, they used about 10x as much loctite as is actually needed. So if you have a 2018, these bolts come out nice and easy. 2019 and up, it can be a struggle. This is where a 1/4" impact comes in very handy.

 

[Dolemite]

I feel your pain @Dolemite. We were just talking about this in another thread (forget the topic) maybe a week or two ago.

The biggest pain is removing or reinstalling the deep recessed screws that together with pushpins hold the thin lip (what Tesla calls the diffuser and is anything but on the Model 3) thats left behind when you remove this rear splash shield.

Whoever thought that was a good design decision fits the stereotype of an automotive industry subassembly engineer.

Yes that was also a PITA. Fortunately, this car remains the easiest I've ever worked on. Nothing like a Volkswagen or Audi which makes you seriously question your existence after performing even basic maintenance.

Tesla started adding loctite to these bolts (same as the ones in the front aero shield and mid aero shield) in 2019, presumably to address the "rear bumper flying off" concerns (which IMO really was just bolts that hadn't been properly torqued to begin with). Unfortunately, they used about 10x as much loctite as is actually needed. So if you have a 2018, these bolts come out nice and easy. 2019 and up, it can be a struggle. This is where a 1/4" impact comes in very handy.

My track record for using impact tools on smaller, problematic fasteners is.... not great.

 

[MasterC17]

My track record for using impact tools on smaller, problematic fasteners is.... not great.

This trick is to pulse it - not hammer it

 

[Dolemite]

This trick is to pulse it - not hammer it

My E46's exhaust system disagrees

 

[MasterC17]

My E46's exhaust system disagrees

Been there - done that! I had many E46's and E90's with exhaust studs that liked to shear into two pieces.

 

[TGuyCanada]

Tesla started adding loctite to these bolts (same as the ones in the front aero shield and mid aero shield) in 2019, presumably to address the "rear bumper flying off" concerns (which IMO really was just bolts that hadn't been properly torqued to begin with). Unfortunately, they used about 10x as much loctite as is actually needed. So if you have a 2018, these bolts come out nice and easy. 2019 and up, it can be a struggle. This is where a 1/4" impact comes in very handy.

I removed the front diffuser bolts quite easily, but there were not instructions saying that its impossible to remove the rear of the 2018 diffuser from the plastic bumper, since there are several bolts holding it from the inside. the whole bumper assembly has to be removed. the bolts were easy to remove with a standard 3/8 wrench. I use "medium" locktite. This was part of my installation of a stealth hitch

 

[medphys3]

This trick is to pulse it - not hammer it

That’s what she said…