Grating sound from gearbox area

[Nick]

Had my gearbox replaced recently with one from a 1.4 Luxe, m car is a 1.2 luxe so i presume they r the same ?

It makes a very coarse grating sound under heavy acceleration, not so much under light acceleration.

The car doesn't perfom anywhere near what it used to. Max possible outta second gear is about 45 ,m when it was more like 60 before. 3rd gear only goes up to about 60.

The clutch also makes a clunking noise when the pedal is pressed e.t.c

I was thinking that maybe the gearbox needs refilling with oil cos we could only get about 1 litre in.

My CV boot has split, could that be resulting in the grating sound (gettin fixed this week) ?

I really hope it's not the gearbox cos my mate did it for me and i can't afford for it to be taken apart again by a garage. !

[mowgli]

where did you get the box from & how qualified was the bloke fitting it?
did you keep the original thrust bearing?
what was wrong with the old box?
did you swap the speedo?

[Aragorn]

grinding noise under accelleraion (in a streight line) is most likely the box's input or mainshaft bearings - if its grinding while cornering its prolly the CV boots

as for the clunking are u sure everythings tightened properly

and what do u mean your getting less performance outta each gear??

sounds like uve gone and fitted a Close Ratio box where your old box was a Wide Ratio box - i guess u dont have a rev counter to compare RPM's??

if not take it right up to the rev limiter (assuming its fuel injected) in 2nd gear - if its a CR box you'll be doing 45mph on the limiter - if its a WR box you'll be doing 52mph on the limiter - having a CR box is actually better for accelleration so its certainly not a bad thing

what do u mean u could only get 1 litre in? after filling it with 1L was it coming out the level plug? if not then its not full...

[Nick]

The bloke doing it has been a mechanic for a couple of years now. He's changed gearboxes on my mates WV e.t.c

The box was from another mate, he took it out of his 1.4 luxe when he got a whole engine.box,clutch from a 1.4SR

The thrust bearings r worn, we knew that when putting it in but it was a case of emergency and i didnt have the means or time to get a new one. It does make that wierd sound when you press the clutch in.

The old box somehow developed a large hole in the housing !

we left the transducer in the new box , and we swapped the top of it over with the new transducer i got with my digidash, so the bottom part is Nova, and the top part is Astra GTE, it all works fine, im sure the speedo is correct, the bottom parts of the transudcers r exactly the same, i don't know why people swap the whole units ovr when installing a digidash, why not just do the easier option and swap the top of it ?

At about 6.5k RPM i could get about 29-30 outta 1st gear, but it sounds very very very very high pitched, with my old box it didn't scream as much. The top end of the car is just about 90 really, 80-90 Mph is a struggle. Previously i could get 105 down the same straight of road that i can now get jst 90 out of.

It just sounds rough as hell

[Nick]

to be honest, i couldn't tell you whether the acceleration is qucker cos my odl box i had normal clocks, with this box i have didgidash and they r completly different, uncomparable. It feels a little quicker tho....

I think it might just be best to take it to a garage and get them to make sure all driveshafts,cv boots e.t.c r all tite n correct and if it persists get the thrust bearings changed and maybe another box put in.

How much does it cost for a box to be put in at a garage ?

One of my twathead mates did sit there trying to start my car without the HT leads connectedand there is a strange noise coming from the cam belt ? maybe my Lack of performance is coming from timing related problems ?

I do have a slpit CV boot, maybe this is causin the grating sound ? coming from the wrong side tho !

I also have a hole in my bulkhead for speedo cable and i lost the rubber grommit, maybe it's just increased sound coming to the interior that's making me worried ?

[mowgli]

different diffs relate to different speedo readings, and digi dashes have been known to make 1.2 novas reach speeds of 130+ mph without anything else done to them......

worn wheel bearings are notorious for making gearbox type noises

A nova box only has about 4 bearings in it they are all easily swappable with a bit of mechanical knowledge. if the box has been run dry, they will knacker.

suspension and tracking will get knocked badly out of alignment when you play will the driveshafts etc. this will adversely affect the performance of your car & also make funny noises. it will also ruin the tyres

[Nick]

yer i'l get the bearings swapped , i know the thrust bearing is screwed.

I've had the Car 4 wheel Laser Aligned this week, what about standard tracking ? i presume they did that at the same time, they did put small matts down with metal padels on them. My tyres did screw up ! need new ones now.

I have a loose wheel bearing on the front left, but it didn't make a grating sound when i had my old box in !

it's not massibly noisy, jst sounds a bit rough, alot rougher than it shoudl be