Love my X5, Hate my speedometer: fix?

[Quacker]

I've been happily in love with my X5 for a long time, but I could never adjust to the speedo error (optimistic). It runs almost 3MPH slow over all speeds and then gets progressively worse, the faster I go. I have varified that it is indeed the speedometer accuracy and the trip computer tells the truth. Most of you (if not all) have this problem too. BMW corporate was not forthcoming on an answer, and man-I tried to get them to acknowledge it.

Is there a fix or mod that I can pull to recalibrate it?

Thanks,
Q

[hayaku]

there's always a 2-5% speedo error based on the different tire sizes (rolling circumference)...

I tested on mine also with GPS and internal speed sensors.. about 3-5 MPH slower then what the speed indicates.

its normal for all cars really...

[Quacker]

Thanks for the input, but what I'm experiencing seems more than that. There is a constant 3 MPH error-even at 15 MPH. On top of this there is a % error so that by the time I'm going about 82 on the speedo-I'm really only going 75. The web is littered with people commenting/complaining about this--including some confirmation that BMW deliberately does this:

"Technical Service Bulletin from 1996 as TSB 620296 which points out that BMW makes the speedometers defective on purpose. BMW's euphemism is "speedometer advance." BMW's speedometers are so bad that this TSB from BMW considers a defective reading as high as 10% plus an additional 2.4 MPH as perfectly OK.

Thus at 60 MPH BMW considers a reading as high as (60 +10% + 2.4 MPH) or 68.4 MPH acceptable. At 70.5 MPH BMW thinks it's fine if your speedometer reads 80 MPH!"


I was just hoping that somene had a plug and drive solution.

[statdoc]

Hmmm....so when I get stopped, and the cop says "Do you know how fast you were going?", I can honestly say "No, I don't."

[Quacker]

Exackwee!

[X5Jay]

Doesn't really bother me, and although I know this is true, I think it makes me drive a bit slower - which isn't a bad thing...

[ROMEO]

I agree with Jay...

[motordavid]

I agree with J, too...on long haulazz trips, it's good to glance at the speedo, see it says "80" or "85" and know I'm not going that fast when the Revunecops come outta the woodwork.

[X5Flyboy]

I noticed my error passing the radar speed signs. My error is a constant -5%.
40 is 38, 60 is 57, 80 is 76actual - easy to check on the onboard computer. Most speedometers have an error. That's why most police ignore you if you are within 5mph of the speed limit. They really want you to be over 10mph, so they can threaten to take your license.