I’m looking for technical help or recommendations on: __Gearbox issue
Hey all,
When I first start the car, the gearbox sounds fine, but after driving for a minute or two it starts to make a chirping sound.
The sound happens ONLY when I accelerate in 1st or 2nd, however recently I’ve been hearing it faintly in 3rd aswell.
In neutral it always makes the sound.
The chirp gets faster with the car’s speed not engine speed.
And finally, it goes away after about 15-ish minutes of driving.
It’s not a belt or pulley issue, and Halford’s said 6000 miles ago that I would need a new gearbox ASAP but the actual smoothness of the shift hasn’t changed, and I haven’t had an issue except the noise.
The gearbox was rebuilt a few years ago.
Is there a common fix for this? New Transmission fluid?
An oil change would be my first and cheapest attempt to solve it. Do the diff oil too, are you sure it’s not coming from the rear of the car, thinking brakes? Who at Halfords said it was gearbox related, has the car been run with the auxiliary belt off, could be a pulley that’s worn then when an increase in speed or when warm it goes away?
Definitely try another oil change first. But those symptoms sound ominous.
My old Humber Hawk did the same chirp/screech with less than half the engine power and twice the body weight, except in top - perfectly quiet.
In that case it was the in-line intermediate bearing between the input shaft (from clutch) and output shaft (to back axle)
I watched the “expert” at a local scrappy fix it in about half an hour after I took the box down to him looking for a replacement box the same. He took one look at it and grinned. I feared the worst.
“They all do it by about 30,000miles. That bearing is a “crowded cluster” of needle rollers, it’s a right pig to assemble. I have an improvement, it’s much cheaper than another old box that’ll soon go the same way.”
He cleaned off the bearing surfaces on both shafts and put in a phosphor-bronze sleeve-bush. It had spiral lubrication grooves on both inside and outside surfaces and was also inset with a few little balls to help pump the lube between them. He was right, it was a vast improvement and outlived the car.