Uncomfortable Vibrations in back seat, but not front at highway speeds?

[MileHigh]

Drove 100 miles home from the dealer with my wife and didn't have any issues. Went to dinner and drove on the highway for about 15 minutes and the front passengers didn't notice anything, but the rear seat passengers said the ride was bumpy and buzzy- very uncomfortable. It doesn't do at up to 45mph on side roads. Going to take it out tomorrow and see if I can tell what the passengers felt. Any thoughts? The back passengers have been on that road countless times in all kinds of vehicles. Travelling about 65mph.

 

[anand]

Tire pressures on the rear?

There is definitely more noise in the rear due to the limited insulation/sound deadening from the flooring in the cargo area

 

[rovie]

Tire pressures on the rear?

There is definitely more noise in the rear due to the limited insulation/sound deadening from the flooring in the cargo area

Yes, I can confirm that. Especially as I don't have windows at the back but panels.

 

[MileHigh]

I'll check tires pressure, I have the Duelers also. The first comment, even before the highway drive, was the noise level- which seems on-par with a Jeep JKL with the rolling softtop.

Maybe we'll have to extend the aviation theme and outfit the IG with Bose aviation noise-cancelling head-phones.

 

[MileHigh]

Did a test drive today with the wife in back. She said it was loud, but not bumpy or ‘bouncy’. It does seem that the IG, especially in the back seat, is a bit louder than it ‘should’ be. That part of the highway does have a bit of an undulation to it. I’m surprised at how the IG transmits fairly small defects in the road surface, but smooth out larger bumps.

 

[Scotsitalian]

Has anyone noticed the amount of steering play in the straight ahead wheel position, mine reminds me of a well worn defender!
I drove a brand new one last weekend and it is much tighter?

 

[DaBull]

Did a test drive today with the wife in back. She said it was loud, but not bumpy or ‘bouncy’. It does seem that the IG, especially in the back seat, is a bit louder than it ‘should’ be. That part of the highway does have a bit of an undulation to it. I’m surprised at how the IG transmits fairly small defects in the road surface, but smooth out larger bumps.

Hi MileHigh, It is a amazing how smooth the Grenadier is off road, however also amazing how you feel every crack on the tarmac. Sometimes it feels like the shock rebound on road is overdone almost making it feel like it is over reacting to the on-road road surface defects. I was wondering if anyone has installed tunable shocks and has dialed back the rebound and if that has helped. Not complaining, just musing. DaBull

 

[Eric]

Has anyone noticed the amount of steering play in the straight ahead wheel position, mine reminds me of a well worn defender!
I drove a brand new one last weekend and it is much tighter?

No issues with the steering (Aug/Sept 23 build), in fact very much like the Discovery 4. The only observation is the turning circle, I have to think if doable when towing a long trailer.
The suspension is harder/firmer in the front and back obviously over the air suspension of L/R but it is more reassuring over undulating surfaces ( ideally suited for our potholed roads )
The noise in the rear is slightly up on coils rather than air but that is to be expected and is not intrusive.
It's a more competent drive than L/R, I like it

 

[MileHigh]

Hi MileHigh, It is an amazing how smooth the Grenadier is off road, however also amazing how you feel every crack on the tarmac. Sometimes it feels like the shock rebound on road is over overdone almost making it feel like it is over reacting to the on-road road surface defects. I was wondering if anyone has installed tunable shocks and has dialed back the rebound and if that has helped. Not complaining, just musing. DaBull

It’s even weirder, that to me I can sense ver small things- like sealant standing proud, but a small pothole, not so much. It’s like the more the suspension has to move, it does better than if the tire is mainly transmitting a very small feature…
Next month I’ll be able to do side by sides with 4Runner, jkl an the IG.

 

[shiv.nandak]

Hi MileHigh, It is a amazing how smooth the Grenadier is off road, however also amazing how you feel every crack on the tarmac. Sometimes it feels like the shock rebound on road is over overdone almost making it feel like it is over reacting to the on-road road surface defects. I was wondering if anyone has installed tunable shocks and has dialed back the rebound and if that has helped. Not complaining, just musing. DaBull

I agree, there is definitely something off about the compression/rebound. I have been playing around with tire pressures and I am noticing that the suspension feels a bit more compliant at higher pressures. For example, I am finding 45psi better than 30-36psi. I am waiting for Dobinson or someone to release 3/4 way adjustable shocks so I can control all the variables.