Differential whine noise gen4 jimny jb74

Hello everyone 
I buy brand new 2020 jimny , I notice a whine noise ( like diff pinion and bearing whine) from the car
I take it to the dealer and the technician take a ride with me to hear the noise and he say it's normal and all jimny have it ! 
Is that really normal?  And do you notice a whine sound in your car (especially at 40+ kmph) ?

All Jimny are loud compared with a normal car. It's not to say that you could have an issue but it would have to be a quite invasive noise. Would you be able to record it and post it to the Internet on YouTube for instance?

I am so glad I fitted a sound deadening kit to my Gen.4. It's no Rolls Royce but it makes a big difference.

Roger

But it will also add a lot of weight..!! Where did you place the sound deadening?

It obviously added weight but probably not more than 20 lbs. I bought it from NoiseKiller Acoustics (UK) ltd. They are in Oldham. The full kit covers the underside of the bonnet , inside the front doors the side panels, the boot well, the rear area under the back seat, and under the front seats and footwell area. They use 4 types of material. Cost was £231 and included a Luxury Welcome mat 75cm x 45cm. I used this for the kitchen door!

Roger

Hi,

I have been looking at that Company in Oldham.
So what is the quality of the materials like..??
Was it all pre-cut, or did you need to cut to fit..??

Cheers,,, Dave

It's all precut and marked as to where each piece goes. I needed to trim a couple of pieces to fit the side panels. They do a fit at your home if you prefer.

Roger

l have to say, l don't hear any whine on our Gen 4 Jimny.
lt's a 2020 one and has done only 3,000 miles. l didn't feel the need to add any extra sound insulation.

We took delivery of our gen 4 two Saturdays ago, the gear whine was the first thing I noticed - it's not a "bad bearing" whine, but it is noticeable, especially if you're coming from a second or third gen GV.

Hey, I have the same and this is kinda obsession for me, so the long story short, after 1k km I’ve changed ring and pinion to 4.625 (HF) after that noticed this weird sound, not sure whether it was before or not. I can hear this noise in between 40+ to 60+ and only when I release the throttle. Do you have the same behavior?
Now I also install reduction gears to t-case (15/104)
T-case became louder, but noise from t-case not so unpleasant as this whine noise when I release throttle.
Tried driving without front/rear prop shaft, so without rear I can hear this noise permanently (just in between 40 and 60)
Any ideas?

If you have changed the ring and pinion and are getting a new noise it's likely because the mesh pattern and or backlash is wrong. Did you set it up yourself or have a shop do it? It's not just a matter of swapping out of old for new, there's tolerances to observe.

It wasn’t me, but guys quite experienced, today I’m checking without rear prop shaft, and now I can hear this sound permanently ( without releasing throttle) between 45 and 60, so can it be diff? I’m about to buy the new (used) one, but right now not sure for 100%