42 lb per Sq In. tires and headlights keep burning out
 

On my Gen 3 Prius, I get the best MPG with the tires at 42 lbs, but road bumps knock out my headlight bulbs. Is there a way to cushion the head lights, tail lights, running lights, etc, from the road shock the harder tires give?

Not sure how they're mounted on the prius, but maybe rubber washers on the headlight mounting bolts (between the body and the light unit?)

Chris

If your getting Sylvania at walmart they are only rated 200 hours. Last one I replaced I got 212 hours based on my average speed and miles. I have 4 Hella long life waiting on the shelf $3 each. Rockauto has a large selection.

I'm getting whatever the Toyota shop puts in. The shop recommended HID, but that's VERY expensive!

Let some air out of the tires.
Breaking stuff to save a little gas is only going to cost more $.
You are likely in the process of breaking other stuff too.

+1 oil pan 4

But, the question is how can I stop breaking bulb filiments, AND keep the better MPG?
Do you have a better answer than "Give up the MPG"?

Get HIDs ;)

The bulbs start at around $10. A full conversion kit can be had for less than $40.

Get LEDs.
Prepare to spend money on the next thing that breaks.

LEDs will do great. I usually get stuff from Super Bright LEDs website.

42 PSI isn't even hard, that's probably not even above manufacturer sidewall limit depending on the tire. Are roads really bad in your area? I could see problems if you lived in Detroit for example, those roads are the worst.

Road condition was the first thing I wondered about.


I literally had a bulb (turn signal) come loose from its socket in the MPGiata last month due to tire pressure. Oh, and due to road condition: I drove a short distance on a very coarse gravel road. "Gravel" is too nice a word for it, really -- more like a "rocky chunks" road. I'm running more than 42 PSI, though.

I have never had bulbs go out from hard tires or bad roads. I have from scraping/smashing ice off of them...

I would try the rubber washers/grommets first.

Is your tire pressure gauge accurate? Many of them aren't. Maybe there is far more than 42 in there.

I would like to see this grommet conversion. Does it involve non-reversible hogging out of all the headlamp assembly mounts? New hardware? What? And when it's done, does it work?

I ran 40psi and more in my off road only Jeep and only the tiny number plate bulbs went - it's been airborne a few time too.

It's all LED now though.

Bulb holders usually have a fair amount of springiness to them, so they don't transfer shocks directly to the globes.

You could maybe try rotating the globes 90 degree so the filament is in their stronger plane?

Could the shocks be dead?

Running 55-60 PSI in my tires has never cost me a single bulb, even on dirt roads. I'd try different bulbs.

It's posible. The car is near 70,000, but they have been going out for years.

Yes, but wouldn't I have to rotate the sockets 90 degrees?

I'm thinking of softer suspension bushings.

If I'm not mistaken, the headlights in the Prius is a bit of a known design issue. Not sure what the root cause is, but again, if I'm not mistaken people have complained about Prius headlights for a long time.

The Prius HID headlights seem to have issues. I've heard it's the ballasts.

https://priuschat.com/threads/my-toy...5#post-2342985

Seems to be a design flaw with a simple fix (I've not investigated it fully though, since I don't own a prius)

Too many volts getting to the headlights, shortens the bulb life. Fix is extra wire to increase the voltage drop slightly?

Check out the link, see if that makes sense...

Chris:turtle:

I had this problem on my cts with cheap led license plate lights. Would burn out very fast in winter when the charging voltage would occasionally hit 15.1v when temps were very cold on an older battery.

There's either a recall or technical service bulletin for the 2010-2011 Prius headlight wiring harnesses, and yes, Toyota's fix is to add length to the wiring. 2012-2015 aren't affected.

2010-2015 Priuses weren't available with HID headlights, only halogen (trims 1-4) and LED (5). The HID issue was with an earlier generation, 2004-2009.

Angel, try the simplest fixes first before you go worrying about expensive modifications like suspension bushings (which, for the record, there aren't any other than OEM-spec available). Try different bulbs first, make sure it's had the headlight recall performed, and report back. It is almost certainly not your tire pressure at fault here.

I just had the car into Toyota for an unrelated issue, and had the FIX done. they also put new bulbs in to prevent old ones from going out due to age. Waiting to see if harder tires bring up the same problem. Thanks to everyone.

Hard tires make one pay a penalty in long-term reliability. Which is what Economy really is. MPG is only an indicator of operator mindfulness.

No road vehicle is designed without tires taking some of the impact. Alter that and pay a MUCH higher price than any putative fuel savings from incorrect inflation.

It also goes straight to the operators physical condition. Why wear one’s self down prematurely? No one is as good at day’s end as at the beginning. NVH deteriorate one’s applied skill.

.

Depending which model year Gen III Prius you have, there is a Toyota recall to modify the headlight wiring harness due to low headlight life. Check to see if your car is covered.

I have a 2010, and am waiting for the dealer to receive the parts to install them.

My Gen III Prius had halogen bulbs in projector housings. I replaced the halogens with HID, and there are 2 plastic covers (which have no apparent purpose to me) in the engine bay toward the fenders that perfectly accept the ballast.

Much better light output, the pattern is faithful to the original, and no burned bulbs.

BTW, I tried LED, but not only did the tabs break off that hold them in, but the pattern was terrible. My experience is that LED works well in reflector housings, and HID works well in projectors.