transmission noise during acceleration and decelleration

[rsnald]

tanong ko lang baka may naka-experience na rin nito, at kung ano ang posibleng problema at solusyon.

on acceleration, usually on 2nd gear or 3rd gear, I would hear this low humming noise, parang hmmmuuunnngggg... sumasabay sa rebolusyon ng makina. It's not comming from the engine, kasi pag nag dis-engange ako ng gear (put back to neutral), biglang nawawala. random yung noise, minsan meron, minsan wala.

on decelleration naman, pag binitawan ko yung accelerator/gas pedal but I stay on gear, usually on 3rd gear, when I use engine braking to slow down, ganun din, low humming noise na minsan parang garalgal...."hmmrrrrruunnggg". ano kaya cause? clutch disk? transmission gears?

tranny experts... help naman. sana simple lang problem

[jeanpierre]

Ano ba ang ride mo rsnald?

[astinagt]

pag naka-neutral wala yung noise?

[theveed]

sounds like a release bearing issue kung MT...

[knight23]

baka sa differential...

[rsnald]

sorry forgot to fill-in other details. my ride is an XTO, manual tranny.
Had my clutch disc, pressure plate, clutch release bearing, and pilot bearing replaced March of last year, after nagkaron ng slippage yung clutch disc ko. At that time, even before palitan yung clutch parts ko, naririnig ko na pero mahina lang. ngayon parang lumalakas. Sigurado naman ako na napalitan coz I was there when the job was done and I bought the replacment parts from Isuzu and took home the parts that were replaced.

[knight23]

check mo yung differential, ask someone to ride sa likod kung marinig ba doon.

ganyan ding yung hiace namin dati, may humming noise coming from the differential kung nag accelerate o nag engine braking.

[theveed]

May flex disc ba ang differential mo? Sa mga lumang Benz kasi eto umiingay... Pero it usually doesn't happen until 150K odo or so.

[speedyfix]

palit ka gear oil just in case never pa napapalitan. use regular oil.

[BeetOls]

eh kapag ang scenario is that you hear a noticeable vacuum sound (parang hinihigop) when you step on the clutch? could it be a problem with the clutch master? i know it's not the spring like squeaky sound na naririnig ko on a wet/rainy day.

and another thing...i also notice that my clutch is slightly heavier/harder when a/c is on...any logic on this? or purely psychological because of the generally heavier engine load on such condition

sorry medyo O.T. yata

[speedyfix]

probably a leak in the master.

but pedal feel should not change with or without a/c

[rsnald]

back to topic...

sinubok kong magpalit ng transmission oil. SAE40 as stated in the manual. medyo nabawasan yung hummming noise pero meron pa rin specially when slowing down using engine brake. I also found out na masyado madami naikarga ko the last time I changed the oil in the tranny. medyo maiitim na rin yung oil after more than 25,000 km. sa susunod, differential oil naman.