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Effect of bad struts on headlight angle

Discussion in 'Gen 3 Prius Accessories and Modifications' started by lex, Jan 13, 2024.

  1. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    Years ago our (a parent's) Gen 3 Trim V began showing signs of bad struts, according to the dealer. We took pass on replacing as it seemed an astronomical sum, and the impact on ride wasn't terrible. However, at this time, I'm wondering if one of the possible effects might be that the car loses some ground clearance at the front (I believe it was just the front struts) and angles downward to a degree. It might also explain the tendency for this model, unlike our other Gen 2s, to bump a front curb in a parking stall with something from the underbody/frame AND the seemingly low headlight angle. The nighttime visibility is not the best.

    How likely might that be?

    I've read in other posts that the Mondo (from Korea) struts are working well. What might be a very rough labor estimate to have a non-dealer shop install a set of two or four purchased separately? Thanks in advance; glad to see the migration completed.
     
    #1 lex, Jan 13, 2024
    Last edited: Jan 13, 2024
  2. nicoj36

    nicoj36 Active Member

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    You can measure your front-suspension height. How many inches in between fender/tire, or from bumper to ground. Then compare it to other priuses.

    Also headlight bulbs do get dimmer overtime. You can adjust its level as well.
     
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  3. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    It's ~2 inches from tire to fender, ~2.5 inches on the rear, and ~6.75 inches from bumper center to ground. This is the trim V model with the larger wheel/low-profile tires, though that shouldn't play into clearances I should think.

    Did you mean an adjustment for headlight angle, not the level of light (luminosity)? Yes, I'm aware and will make angle adjustments, but was attempting to establish if it's connected to struts failing. Would be interesting if there were a luminance adjustment.

    As we learned elsewhere on the forum, bulbs in these early LED headlamps in trim V are non-replaceable; addressing thia would entail replacing the full headlamps assembly ($$$). However, these early LED designs were intended to last a very long time, perhaps the life of the car. How that's possible is unclear.

    Attempted to add measurement pics but that function doesn't yet seem to working at the moment.
     
    #3 lex, Jan 14, 2024
    Last edited: Jan 14, 2024
  4. bisco

    bisco cookie crumbler

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    pic upload has been broken for awhile. people have resorted to linking offsite pics
     
  5. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    I see - the measurements above can convey info in this case, fortunately. Replacing profile pic with any shot needed is also a workaround option.
     
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  6. bisco

    bisco cookie crumbler

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    do the struts hold up the car, or the springs?
     
  7. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    A mechanic, 3 years ago and again 6 months ago, noted the strut issue (we were not aware at first) and, in second instance showed us some leakage around the strut. I'm not sure how to answer whether the strut holds up the car or the spring - how can I know? The car drives fine until you hit a pothole, good bump, or very rough patch - then the terrain isn't absorbed properly by the suspension. It's rough and a little noisier through the cabin from the front, it sounds. Driving smooth roads, streets or highway, there's no trace of an issue.
     
  8. AzWxGuy

    AzWxGuy Weather Guy

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    To my knowledge the hydraulic strut is only there to dampen oscillations. It doesn't support the vehicle weight or contribute to what is supported by the suspension. Springs and such. Worn struts have a negative effect on various things like steering and maintaining wheel to road contact in addition to more rapid wear in the suspension system as a whole. Wondering if this early LED system had a leveling sensor like the HID system had. It was located on the rear axle. The device was prone to road salt corrosion, loss of lubricant and breakage.
     
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  9. bisco

    bisco cookie crumbler

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    if you need struts, get struts. there are plenty of alternatives to the dealerships.

    if your lights are not pointing correctly, or there is suspension wear or damage.

    the gen 3 underclearance may be different than gen 2, you can look that up.

    if the car height is incorrect with correct tyres pressure, it's probably worn springs:

    Automobile-Chassis.html
     
  10. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    Thanks - and I wasn't aware of the possible existence of a leveling sensor to the lights - will investigate. This may help explain matters.
     
    #10 lex, Jan 16, 2024
    Last edited: Jan 16, 2024
  11. lex

    lex 2010 trim level V Prius & a 2005, always garaged

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    I missed the rhetorical earlier, and understand now that struts only dampen oscillations while springs support the car. Will investigate a possible underclearance difference between gen 2 & 3 - have long wondered about that, and brand recommendations on struts in the appropriate forum subcategory. I didn't quite follow what was meant by "if your lights are not pointing correctly, or there is suspension wear or damage."
     
    #11 lex, Jan 16, 2024
    Last edited: Jan 16, 2024
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  12. bisco

    bisco cookie crumbler

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    LOL, i have no idea what i meant :p

    the lights can be adjusted if they are pointing incorrectly, but you should probably make sure the suspension is correct first. that would require a suspesion shop i suppose.
     
  13. AzWxGuy

    AzWxGuy Weather Guy

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    If there is a sensor then it will be visible when looking under the back of the car, on the rear axle a little left of centerline.