Following on from the useful discussion on car LED bulbs on O-N's Ol' Blue thread, I thought it might be useful to pool the info on here - perhaps peeps who have them fitted can point us in the direction of the exact - or best - ones to use?

(On a connected note, Ken said: "for about the last 16 years, on perhaps 90% of the journeys I've made, the car I'm driving has been towing a trailer. I've never fitted extra relays, just standard A series flasher units, with no problems regarding longevity of those items... If anything has been affected by extra current draw from a trailer board, it's been the brake light switch, which is why there's a relay fitted to that circuit on all of our Dyanes... Ken"

Does the indicator flash rate not speed up dramatically with the additional filament lamps joined in, Ken? I'd have thought that LEDs would have the added benefit here of not changing flash rate, as well as simply not adding significantly to power drain.)


Which LED bulbs have people used in their cars? Any recommended suppliers? (There are 1,000's out there, and I can't help thinking that some of them are border-line useless).

Ta much.

IMHO, LED bulbs are best left for lamp assemblies designed for them. Our cars have small reflectors and the very directional nature of LED bulbs means that a lot less light goes to the reflector. Although the bulbs themselves appear brighter, in real life they look dimmer when used in a regular reflector and that's a lot less than ideal when our cars have such puny rear lights to start with.

Just my ha'p'orth

(Apologies if this has been mentioned/covered at depth in the other thread you refer to: I missed it).

My experience has been different. I haven't tried putting 10w ordinary bulbs in as Ken recommended so I can't offer a comparison with that option. One thing that I noticed was that despite sealing them down the insides of my rear lenses were always full of dirt from road spray, ensuring that those are regularly cleaned on the inside as well as out can make a difference on its own.

I bought two LED 25 facet bulbs from ebay and before I fitted them I polished the reflectors as high as I could get them. (On my 'old' car I just wrapped some tinfoil over them shiny side up) The LED's I have are actually multi-directional bulbs, so they scatter light in all directions as well as aim it directly outwards.

The improvement I noticed was quite clear, because to begin with I fitted just one so as to compare them side by side. As I say I don't know if they are better than fitting a 10w bulb to replace the weedy original, but they're a damned sight better than original.

Excellent idea for a thread. Thought I'd add my thoughts and experiences.

I have experimented with LEDs at the front, to replace the sidelights, however I found them to be pretty uneffective sadly.

The rear is a different story. The LED side lights are superb - mine are not multi directional ones, but are very bright indeed. I also added an led high level break light. I'm slightly neurotic about being hit from behind now so I like to be bright at the back. LED breaklights have the advantage that there's no 'heating up' time so they come on quicker and are much brighter.

In order to fit LED indicator bulbs you need to either fit a resister to each indicator, or (better) fit a 'clicker' designed for use with low voltage leds. If you don't you'll find they either wont flash or flash weirdly.

The most success I've had with LED bulbs are the ones fitted to my boot box. These are LED clusters that provide break, side and indicator functions. Very effective and very bright.
http://cgi.ebay.co.uk/LED-3-FUNCTION-12V-TRAILER-COMMERCIAL-CARAVAN-LIGHT-/300487031311?pt=UK_Trailers_Transporters_Parts&hash=item45f66c3a0f#ht_716wt_792
I was lucky to get a pair for £24

My next intention is to add the matching reverse light:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=390261598552&ssPageName=STRK:MEWAX:IT#ht_1836wt_1026

Quick addage to the above - if you have LED trailer lights you don't need to add additional resistors. My boot box is wired into the trailer socket (for easy removal).

i had written a blabering response but ive lsot it so i will re write it as best as

sam could you not simply add led bulbs into the existing trailer board bits?? be cheaper???
i found thses
http://cgi.ebay.co.uk/21-LED-AMBER-ORANGE-INDICATOR-BULBS-581-inc-RESISTORS-/110560002164?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item19bde3c074
come with resistors,

im quite up for putting led brake lights into the rear brake lights,
and especially my trailer board. i tend to find it takes a noticable amount of small time for the brake lights on the trailer board to light up, and they sort of gently come into light, like a dimmer switch being turned up very quick, so im thinking of bunging some led's in there..
what about led's in the rear headlights??

rear headlights...?!

James, the resistors are only required if you are replacing your car's indicator bulbs with LED ones. As samfieldhouse says, without them your existing indicator relay (clicker thingy) simply won't work (they rely on a hefty current to heat up a bi-metallic strip inside which bends and breaks the circuit. It then cools and bends back to remake the connection. It then heats up and bends again...click...click...click).

So, to replace your CAR's indicator bulbs, you either DO need to fit resistors (which allows the same current to flow around as with the old bulbs) or else fit an electronic 'clicker' which doesn't need this current - so no resistors required.

If you simply plan to use LED bulbs in the trailer light board then, in theory, you can just wire them in to your existing car's wiring with NO extra relays OR resistors required - they draw such a small additional load that the existing wiring will more than handle it perfectly well.

what i mesant DA is the rear lights, you know what i mean!!

well im going to put led in trailer board and in the rear lights indicators etc,
i think!!