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My car has been rather sluggish lately - both ABS and TCS lights are on, which means there is a sensor error somewhere. I haven't had the time to look for and fix said error, but I have had to drive here and there. In doing so, I often find myself shifting my automatic transmission to 1st gear and then up to 2nd, 3rd, and finally D in order to get up to highway speed (60mph). Is this okay to do? I typically hold RPMs as such:

GEAR    RPM    Action
1       5000   *shift*
2       4000   *shift*
3       3000   *shift*
D       2500   *cruise*

This gets me up to about 65mph, if I were to not do that, it would only get me up to about 30mph in D (usually gets stuck in 1st). Pretty sure my wheel speed sensors are gone.

Car is a '97 BMW 528i with 171k miles on the clock, purchased at 154k on the clock, engine head rebuilt at 168k.

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Wheel speed sensors would explain the ABS & TCS problems, but shouldn't affect the transmission. Does your transmission fluid smell burnt? Is the level OK? Does the car shift normally at lower speeds? Shifting an automatic manually doesn't hurt anything (unless you downshift at too high a speed or something), but it's hard to say what might happen with a potentially already-damaged unit.

  • Not that I can recall...I've sent the car off to the mechanic, but don't recall the Trans fluid smelling burnt. And nope, never downshifted at too high a speed – jsanc623 Jul 23 '12 at 15:35
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I've rebuilt a few transmissions (actually a lot of transmissions LOL) and no, manually shifting is just fine. All your doing is replacing the TCU with your own shifts. So your just fine manually shifting the car.

WOW just saw this was a four year old question... sorry folks.

  • 4
    There's nothing wrong with answering old questions here. Just make sure you're answer is good, detailed, adds something new, and is based on facts or relevant experience. – user568458 Aug 1 '16 at 10:08

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