I drive a 1998 Montero Sport 3.0L RWD A/T.

Q1: I've been hearing a high pitched squealing noise coming from my bell housing when idling in gear for a couple months now and I can't figure out what it is. I've checked the fluid level of the tranny and it's fine. I've also changed the fluid and filter since the noise began but it did nothing for the noise. It's not a belt up front, no belt noise under the hood but you sure can hear it under the car or next to it. I can hear it super well when I'm next to a wall or large vehicle. I've taken it to several mechanics and none have been able to figure it out either. My research shows it very well could be the torque converter on its way out, I need some thoughts on this.

Q2: Strong ethanol like smell coming from exhaust after driving around for a few hours. I deliver food with my Monty so it gets a lot of mileage and daily use so this smell is becoming a nuisance and a worry on my mind. It seemed to go away after I replaced the cat but it could be that I gassed up somewhere else which eliminated the smell. Thoughts on this one is welcome as well. I've been filling up at a store called "RaceTrac" with regular grade 87. I have also changed the O2 sensors with OEM Denso units, and no codes are present.

 

Bellhousing noise - transmission input shaft bearing?

Don't know where ethanol smell would be coming from. Gremlins having a beer party and not observing social distancing? Usually a bad or defective cat results in rotten egg (sulfuric) smell.

 

An interesting idea, never thought about the input shaft bearing.

The next time my coworker saying anything about the smell I'll tell him I found the cause!

 

Ok now I hear three distinct sounds that I believe are coming from the torque converter or maybe the input shaft bearing. Upon cold start/before tranny is warmed up, there is an odd hum/grinding noise that occurs like clockwork every 1-2 seconds apart and sometimes accompanied by a very distinct but random vibrational humming noise like the sound a wine glass makes when you run your finger around the rim of the glass and it's quite loud. After the transmission begins to warm up these go away and is eventually replaced by that hissing noise I mentioned earlier once it's up to operating temperature. I found this website with a diagram of the transmission just in case anyone needs to order parts or simply look at it for diag. I believe part#650 is the input shaft bearing and race. https://www.automaticchoice.com/en/a...arts-catalogue

Other than these noises, the transmission still shifts like butter and I have no issue with TQ shudder that I'm aware of.

 

Naeos, sorry you are still having issues. With transmission, the problem is - you can't simply replace a little part and get your issue resolved. If you are there for a penny, you are in for a pound. If transmission drives and shifts OK, just keep driving and don't worry about it. You may want to follow Click and Clack's advice on dealing with external/annoying noises and sounds - turn up the radio...

 

You can't tell me what to do! /s
Anyways, I'm probably going to pull the transmission sometime soon because I have an upper oil pan leak that's getting out of control(easier then pulling engine), so I'll have a chance to take a peak and see if I screwed something up when I put the new/used engine in, maybe the noises are from a bolt working loose or something.