3

I'm hearing rattling noise when the transmission is engaged (drive) and it get's louder at higher rpm. previously I did not hear this. There is no noise when I rev engine in park mode.

The gear in normal case would shift as RPM exceeds 1500rpm, but now the gear shifts at 2.5k rpm when it's in constant acceleration, if I speed up and expect sooner gear shift , it does at 3.5k to 5k RPM.

could it be drive belt that is rattling? any transmission digital adjustments.

Please let me know if you need any other information.

  • I read a post about chain tensioner degrade/failure symptoms. promini.com/technical/cooper_r56_death_rattle.php. But I don't hear rattle noise in park only in drive. but it does comes down when I drive at higher gear and low rpm – cyborgt8 Apr 19 '16 at 18:49
  • Could you have a look at this sentence, "The gear in normal case would shift as RPM exceeds 1500rpm, but now the gear shifts at 2.5k rpm when it's in constant acceleration, if I speed up and expect sooner gear shift , it does at 3.5k to 5k RPM." If you could break it up a bit and clarify, it's confusing me a bit. Cheers! – DucatiKiller Apr 19 '16 at 20:03
  • Before the noise started, the gear shifts from (2->3,3->4,4->5) if there is constant acceleration(in order words continuous gas pressed ) for a time much shorter than how the gear is shifting up now. . there are two cases in current context , a) when I drive leisurely the gear shifting up takes much longer time although the gas is constantly pressed and only after it exceeds 2.5kRPM . b) now if I have to speed up 50mph from a stop point , I have to rev engine above 5kRPM because the I can notice that the transmission is still in lower gear. (2,3). – cyborgt8 Apr 19 '16 at 21:36
  • Bottom line engine revs high and gains enough speed for gears to shift up but it doesn't shifts up causing traffic slowdown for people behind me who can rev and gain faster speed. – cyborgt8 Apr 19 '16 at 21:37
  • Also , I have noticed that when I use paddle shift the gear change is instant and doesn't take long. – cyborgt8 Apr 21 '16 at 22:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.