My last post was all about upgrading visibility up front in the headlights. I figured, why not check out the back? 👀 But seriously, why have I waited 6 years to do this!? Out back there are 4 lights per side.
What was good for the front is good for the back - I'm talking LEDs!
Headlight upgrades across the board - worth it!
After my last post, and a few weeks of driving, while I liked the LEDs they just didn't have a long-term benefit that I was hoping for. I opted to return them and went for an insane update. With all the rain in NorCal, the nights have felt darker than usual, maybe it's just my old eyes 😆
Here's the upgrade list that I used to update ALL bulbs in the headlight, believe it or not there are 4 modifiable light sources in there.
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| Left to Right: Amber Turn Signal, Green Turning Light, Red Headlight, Amber Marker Light |
I'll breakdown the replacements, and let's start with the easy ones - the side marker lights!
These are a pretty common 194 LED replacement. The implementation in the headlight is interesting as the bulb holder aligns with contacts in the actual headlamp, so you can just swap bulbs and snap the holder back in place.
| this squigly thing is the side marker bulb holder |
| you can see the 194 bulb and the contacts on the holder |
| quick comparison of 194 vs LED size |
| swapped in the LED |
| standard incandescent bulb |
| new LED bulb, much brighter! |
| very pricey, but extremely bright HIDs from OSRAM |
crazy bright, even at dusk! | ||||
The next light was the most challenging of the bunch, the turning/directional lights are a size I've never worked with previously. This makes it part of the challenge. The PSX24W LED socket has two tabs that you push in and the socket is removed. The big problem with the headlights is that you cannot get your hands in there, at least I couldn't fit my hands. I opted to use some curved pliers for a while, but ended up snaping off the tabs which let me remove the socket - at least I could swap the bulbs now!
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Upgraded to LED headlights
One of the HID bulbs I used back in 2019 burned out, so with newer LED technology I upgraded to a new set of D3S LEDs. OPP ULITE D3S Led Headlight Bulbs, 3RD-Gen 100% Plug & Play, Canbus Error Free, 6000K White 70W 8600LM Headlights Bulb, Replace OEM Xenon Bulb
It's always a good time to change your cabin filter!
After all the fires this past summer in NorCal, I decided to check the cabin air filters in our cars. All I can say is O-M-G that's NASTY! You can get a cheap $10 filter like the FD920 Cabin Air Filter for Ford Focus, or upgrade to a nice HEPA based one like the PureFlow HEPA Cabin Air Filter PC6174HX
Whatever you do - just do it! Look at our old filter compared to the new one! Seriously disgusting!
If you don't know how, it's a really simple process on the Focus family. You just need one torx bit and everything else is pretty much hand driven.
Michelin Pilot Sport All Season 4 - great option for performance all-season tires!
Our Michelin Pilot Sport 4s finally were at about 2/32nds and had to be retired at 32k of usage, so at least they met the warranty lifetime of 30k! My wife is about to start a new job where there may be more 'weather' to deal with so we opted for the Michelin Pilot Sport All Season 4s to replace them with. The tire is excellent, great ride quality and the grip is darn good!
These tires have a 50% upgrade in warranty to 45K so that's a benefit as well for longevity. Only 54K on our 2016 FoST and loving it!
Overall, we stuck with the 245/40R18 size for a little width gain from the stock 235 size. We've been really pleased with them so far!
Upgraded to Diode Dynamics SLF LED Fog Lights
Replacing the D3S HID bulbs in the Ford Focus ST
The stock HID ballast in the ST3 are Osram 35W, so that's already good (as compared to older 25W versions) There are the usual HID replacement parts, and boy can they be expensive!
If you know the HID Kelvin color chart, 4.6K from the Osram is a decent HID coloring (as shown below) to see well, if you go too low you're yellow (good for fog lights), and if you go too high - well, you turn into ricer purple, heck I've even seen some guys go to 30,000K and it's HULK green!





