Thread: Road noise transfering into cab???

Q: what type of noise... Metal squeaking / grinding / whirring?..... What tyres you using... Condition of springs / shocks... What type of noise on humps... @ what speed.... Windows open / closed/ window wind deflecters fitted...roof rack fitted......bit more info... Is the sound suppresion in place around transfer case tunnel... If after market cdl fitted this may have been removed....
James

The noise is as stated the road noise feels like it is traveling straight through the suspension into the cab.
Like a dull roar or drumming of the road surface.
When you go from smooth bitumen to coarse etc on open highway it is really noticeable. Not really noticed at lower speeds around the city.
Windows up. AC on.
Has 4 new BF Goodrich AT's 235 on steel rims.
The banging in the suspension is worst when hitting pot holes etc. A real solid bang. May need shocks. The ones fitted look to be original so maybe they are shot.
Its as if the cab is mounted straight to the chasis!!
Only had the car a day or so. Will change out engine/gearbox mounts and go from there.
Probably a hard one to sort out with out hearing it.
Just thought someone may have had similar issues.
Thanks

Mate, from what you are saying I would be looking at Shocks being the problem.. Also have have a look at the springs and make sure thete isnt a broken one... Cos if the shocks are that stuffed a spring may have broken with large pot hole strikes... Either way get it properly checked as driving in certain conditions with dead shocks cud leave u dead... Might be a nice time to get a lift as well!!! Just think that whilst the suspension isnt working well you could be doing damage to the other steering n suspension components as well as your tyres... James

Hi there,
Road noise can be pretty tricky to trace but there can only be 2 transfer paths - airborne or structureborne.
If you're happy that the tyres are good, no uneven castellations on the edge of the tread and assuming all the door seals (especially the rear doors) are good, then it seems like you're definitely describing structureborne noise.
There aren't that many paths for the noise to get transmitted on a beam axle car and from what you said about noise over speed bumps, I'd check the rubbers on the shocks and all the suspension links. There's also a plastic cup type thing on the top of the spring, or at least I think there is on my D1. That may be broken or missing.
Dunno if the D2 has rigid body to chassis mounts or if they're rubber isolated, but that's worth checking out too.
From recent experience, the propshaft UJs can start to make a vaguely roadnoise like rumble when they are on the way out!
HTH but like you said its hard to tell without listening to it

Cheers

Dan

Thanks for the comments, a friend mentioned the insulators on top of the springs may have rubbed thru.
Shockies are next after engine/gearbox mounts.
Springs look okay, but a lift sounds good!!!
Wealth of info on here.

Will look at double cardan shaft. Replacing rear coupler anyway.
Got the parts out of england heaps cheaper than here!!
Love that aussie dollar at the moment.

Check all things you have mentioned but a quick visual of the front prop shaft I would recommend.

Place in neutral and just spin it. There is a good link in the Good Oil regarding the front prop shaft.

Regards
Andrew

If I can add.......my 04 D2a Classic is in 8/10 condition, has only 165K and I baby it with servicing and use it only as a 'town-car'. It has a 2" lift and apart from me getting rid of EGR and exhaust cat, it's stock (I also have an 02 which is the 4WD war wagon )

However, when I got the 04 last year, it had 4 near new tyres on it (Don't want to bag them but the brand name sounds like 'Bloopers') that I thought I'd keep on and run them until replacement.

The only thing is that they are soooooo NOISEY! They transmit every road irregularity, uneven surace and different mix of bitumen road surface noise straight into the cabin.

All of my seals are in good nick as are engine mounts etc, etc.... I've swapped the tyres off the war-wagon (BFG Muddies) for a comparison and blow me down if they don't produce as much road noise!!

I borrowed my mates 2000 D2 steel rims with the original Goodyears and the car is whisper quiet.....

So in my case - I'm stuck with a noisy car until I replace the existing tyres

P.S - that's the only real complaint with the 'Bloopers'

Ok,
Changed 2 broken engine mounts. Not as difficult to change as it looked at first. The Drivers side mount was a bit of a mission, easy to fit the new ones as the studs unscrewed, unlike the old mounts, luckily they were broken which made it easier to get them out.
Changed 1 broken and 1 nearly broken gearbox mounts. These were easy compared to engine.
How the car managed to have all 4 broken mounts is hard to know!
This improved noise but it is still there.
Changed rubber coupling on the rear drive shaft.
Suspension is removed waiting for lift kit to arrive from UK.
Will test drive after lift and new shocks fitted.
The shocks/springs are all original equipment so hopefully this is the fix.
Found shock mounting points torn on front shocks. Still had build/assembly line stickers on them from 2/2000, amazing....
Suspension came apart very easily. 2 hours she was all stripped out.