Help with 91 Cadillac Seville STS

Hey all, first post.

So, i recently wrecked my daily driver 61 Baja Bug, and a buddy gave me a 91 Cadillac Seville STS, and the low-beam lighting is absolutely terrible. i feel like i can barely see the road. hi-beam works great, and in this model there are four separate 9004 bulbs in individual compartments for lighting up the headlamps, each only firing half the bulb. I had a spare brand new pair of 9004 philips bulbs (the basic pair for cheap at all the auto parts stores, forget the specifics, its been a while, they were only used once, then put away) that i swapped in and it made no difference. i parked the car in the warehouse at work (level surface with a flat wall to point at) and verified that they are aimed appropriately. the headlight housings look practically brand new, are made of glass, and the reflectors are clean, no hazing or fogginess at all. I know better than to add supplemental (snake oil) fixes like HID kits, fog lamps, etc. I get 14.29 volts at my battery, and 14.22 volts at the socket, engine running, so i don´t believe a relay would be necessary...

Will a pair of Xtravision or Silverstar bulbs be worth the money? Any other suggestions?

My Baja had Cibie Z-beams, so am I just spoiled? that car had the best lighting of any car i´ve ever driven.


Here´s the car in question, btw...

Lingwendil said:

Hey all, first post.

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Welcome to the board!

i recently wrecked my daily driver 61 Baja Bug

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Yikes. Sorry the car's wrecked, but glad you walked away.

a buddy gave me a 91 Cadillac Seville STS

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That's quite a change from a '61 Baja Bug.

and the low-beam lighting is absolutely terrible.

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Yes. That quad-9004 setup was one of GM's dumber ideas from a functional standpoint. The beancounters loved it -- the reason why they did it was so they could use the high beam filament of the inverted outboard bulb as a "free" (and minimally-effective) glare shield for the low beam filament.

I know better than to add supplemental (snake oil) fixes like HID kits, fog lamps, etc.

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Hallelujah!

I get 14.29 volts at my battery, and 14.22 volts at the socket, engine running, so i don´t believe a relay would be necessary...

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If you pull the socket off the headlamp and probe it, the result you get doesn't tell you anything because you're measuring the circuit unloaded. Your voltmeter draws almost no current, so you're not seeing the voltage drop in the circuit under load, which is significant (because GM cheaped out on the wiring just like they cheaped out on the lamps).

Will a pair of Xtravision or Silverstar bulbs be worth the money?

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Forget that Sylvania junk, see this thread. The best 9004 bulbs are these or these, but if you can scrape up a bit of money, you can have a much better fix. It just so happens there's a pair of export headlamps for that car on Ebay right now, brand new: left side, right side, brackets and all. They are Italian-made Carello units, considerably better than the domestic junk, with an H4 high/low beam and an H3 (maybe H1) fog lamp outboard. The contour lines of the glass don't match up with the body lines of the car quite perfectly (picture here), because GM bought something off-the-shelf from Carello rather than commissioning a made-to-order lamp (typical GM cost-cutting again) but if you can live with the minor gaps, you'll wind up much happier while driving at night.

You'll still want relays, not only to eliminate voltage drop but to adapt the single-H4 headlamp in place of the dual-9004 unit on each side. Use Osram 70/65w H4 bulbs, have the lamps aimed to "VOL" specifications, and you'll have night seeing better than you had in your Baja Bug with the Z-beams.

If that's too much money, then you'll have to make do with what you have. The 9004 bulbs linked above and a good relay kit. That won't make them good, it'll just make them a little less lousy.

Here´s the car in question, btw...

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Can't quite tell from the photo, but looks like the rear springs might have some sag to them, too.

I would LOOOOOOOVE to put H4 bulbs on this thing, and in a couple weeks i can probably grab a pair of those export housings, i was hoping there would be something similar. No-load sure doesnt tell much, so i think making up a relay harness wouldnt be a bad idea at all then, i think i might even have some relays lying around. Thanks!

The car has an air ride system, and im pretty sure that theres a sensor somewhere that nneds adjusted or serviced. oh the joys of poorly over-engineered luxury eh?

Lingwendil said:

Hey all, first post.

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Welcome! Thanks for choosing a good subforum to make that first post!

So, i recently wrecked my daily driver 61 Baja Bug, and a buddy gave me a 91 Cadillac Seville STS, and the low-beam lighting is absolutely terrible.

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Ouch! A 30 year leap forward, though. Fuel injection, antilock brakes, air conditioning...

in this model there are four separate 9004 bulbs in individual compartments for lighting up the headlamps, each only firing half the bulb... the headlight housings look practically brand new, are made of glass

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At least they didn't cheap out on the lenses-- but still, they really messed up when they designed those lamps.

Will a pair of Xtravision or Silverstar bulbs be worth the money? Any other suggestions?

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At Wal-Mart in a remote town, needing a bulb to get home with, the Xtravision over the SilverStar Ultra-- but when you have the luxury of time, the X-Treme Vision or the NightHawk Platinums as linked above are the way to go.

My Baja had Cibie Z-beams, so am I just spoiled? that car had the best lighting of any car i´ve ever driven.

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Similarly, my low beam driving is amazing with the Hella XL auxiliary low beams on my Previa.

Other than the sag, that's very, very clean, and perhaps the fix for the suspension isn't that bad. I'd jump on those Carello units, but then again, I know my own finances better than yours. If you plan on driving that Cadillac very long, though, the extra comfort from being able to see on low beams could well be worth it.