309 diesel manual. When driving on the straight a loud whining sound occures. The sound is temporarily remedied by pulling up and turning the steering wheel on full lock. After doing that the sound dissappears for a while. It only does it on a straight journey never around town. This has been an increasing problem for the last 9 months. Is it gearbox or a driveshaft?
transmission whine
- Thread starter pullgees
- Start date
Just a guess but I would point the finger at a driveshaft CV turning the wheel fixes it would indicate some wear that is temporarily relocated by the movement, hence around town more corners = no noise. 
cruiserman said:Just a guess but I would point the finger at a driveshaft CV turning the wheel fixes it would indicate some wear that is temporarily relocated by the movement, hence around town more corners = no noise.
I'd say yes that must be it right but the sound also dissappears if I depress the clutch or flick it in neutral while on the straight. If it were a CV joint why would it go quiet out of gear, coasting? Put it back in gear and the noise starts up again.
Just to go over it again in more detail. The noise will start up on a straight run maybe fifteen minutes into the drive but this is decreasing in time as whatever is wearing is wearing more. The noise is in all gears. What triggers it is if I have to take my foot off the accelerator then the noise starts. When I depress the accelerator the noise continues in all gears. Only when I do a sharp turn or get into town where I am turning all the time does it stop.
wierd... CVs dont whine in my experience, just clunk and click whilst turning.
If its in all gears, in wont be a worn gear, but could be a worn crownwheel/pinion, layshaft, diff carrier or wheel bearings (whine road speed reactive) or primary shaft (engine speed) bearings
If its in all gears, in wont be a worn gear, but could be a worn crownwheel/pinion, layshaft, diff carrier or wheel bearings (whine road speed reactive) or primary shaft (engine speed) bearings
Haakon said:
Weird indeed. It can't be wheel bearings because the noise ceases when coasting out of gear. If it were a gearbox problem why would turning the steering wheel stop the noise? If it is a CV joint why would it cease its noise out of gear. What I'm faced with are two facts each one counters the two possible faults gearbox or CV joint.
When was the last time you checked the level of oil in your transmission?
I had a strange one like this in a CX Citroen a few years back. That one started if you sat your hand on top of the gearstick in 5th gear as you were pulling up. It turned out that the box was almost empty, but it's a long story how it got that way.
It could also explain why turning the steering makes a difference at it places different straains on various bearings and hence relocates the weight on balls in their races.
I'd drop the plug out of the bottom & refill and depending on the oil recommended possibly take the precaution of including a gearbox additive on the refill.
Alan S
I had a strange one like this in a CX Citroen a few years back. That one started if you sat your hand on top of the gearstick in 5th gear as you were pulling up. It turned out that the box was almost empty, but it's a long story how it got that way.
It could also explain why turning the steering makes a difference at it places different straains on various bearings and hence relocates the weight on balls in their races.
I'd drop the plug out of the bottom & refill and depending on the oil recommended possibly take the precaution of including a gearbox additive on the refill.
Alan S
Alan S said:
Plenty of oil in the gearbox. I can't see how the steering can move races or gears in the gearbox unless there is some lateral movement with the driveshaft housing in the gearbox through wear. Normally that should be solid. The only designed lateral movement is in the driveshaft itself, in the CV joint. But if there was lateral movement with the housings wouldn't that disturb the oil seal?
But I come back to the old problem how come the noise stops when I take it out of gear even at 70mph.
When the car is in neutral, the engine is not driving the gearbox, the car is due to it being on over run. This should eliminate the wheel bearings.
The lateral movement of turning the wheel via the steering is what I was referring to.
I'd still start at a gearbox oil change. It might even be interesting to see what comes out on the magnetic plug. I'd consider that the cheapest of all ways to start trying to pin point the problem. Much cheaper than a transmission strip down.
Alan S
The lateral movement of turning the wheel via the steering is what I was referring to.
I'd still start at a gearbox oil change. It might even be interesting to see what comes out on the magnetic plug. I'd consider that the cheapest of all ways to start trying to pin point the problem. Much cheaper than a transmission strip down.
Alan S
tasgill said:
Did your noise continue while coasting in neutral? If it were tyres the noise should continue out of gear. This noise happens on different tyres anyway.
I take it you referred to the intermediate support/bearing half way along the RH driveshaft. Can I feel for play there or do I need to take the drive shaft out to check? When I change the oil next week I'll give it a waggle.
I did fifty miles today mainly on straight roads and the loud low pitch whining was absent. Another day I only need to do a few miles before it starts, it's bloody ridiculous.
A rust ring around the seal on the driveshaft bearing would be a good indicator. Apart from that I guess the only other way would be to remove it for inspection. Tyre noise can be a real PITA to pick, but I wouldnt expect it to vary hugely when you put the car in neutral.
Does the noise vary much when you when using the brakes?
Terry
Does the noise vary much when you when using the brakes?
Terry
tasgill said:
Thanks. I haven't paid attention to any change while braking or after braking, I'll listen out. I do have a slightly sticking caliper on the RH side but if the pads were still in contact with the disc the noise would continue out of gear.
The noise has gone away all by itself. Last week it did it nearly everday and the last time was last Saturday. I can't figure it out at all. Anyway regardless I've changed the gearbox oil. There were no metal shavings on the drain plug and I even ran a magnet through the waste oil in the bowl and nothing. The oil was clean and did not need changing.
The RH driveshaft centre bearing feels good, no play there. The gaiters are good , no splits and signs of grease escape
The only other thing I can think of is that I do have a sticky RH brake caliper. But if it was pads occasionally rubbing on the disc the noise wouldn't go away when the clutch pedal is depressed or taking it out of gear and coasting. A motoring mystery.
The RH driveshaft centre bearing feels good, no play there. The gaiters are good , no splits and signs of grease escape
The only other thing I can think of is that I do have a sticky RH brake caliper. But if it was pads occasionally rubbing on the disc the noise wouldn't go away when the clutch pedal is depressed or taking it out of gear and coasting. A motoring mystery.