borg warner model 12 noisy

[keri]

Hi all just completed my restoration of a 1975 xjs fitted with a 3 speed borg warner model 12 auto box I m trying to iron out a couple of rattle/vibrations etc as its the first time on the road in 28 years but it has been completely overhauled except the gearbox the reason being I was told by a previous owner that it was rebuilt just before going of the road in 1989, well it was stored clean and dry I took of the sump and it was very clean no debri or bits so replaced the gasket and give it a paint and it looked the business, but now reinstalled and up and running it has a nasty whine noise, oil level is correct and gearbox selects all gears normally and smooth inc reverse with so slippage but today I discovered if you select 1st on stick and drive in whines and gets louder when throttle released ie overrun 1st gear. when I select 2nd it does the same but not so loud but it is there in 3rd it seems fine anyone any ideas as it looks like I am going to have to remove it for a specialist to sort but I would like to have an idea of what it is so im not given the run around,
many thanks
keri

[ptjs1]

keri,

Sorry to hear of the problem (although great to hear that the car is moving!!).

I'm sure there will be others who have more experience of the BW box. However, before you take it out of the car and cognisant of its 28-year layup, I would be tempted to do a fluid drain and refill and change the filter. Because of the torque converter and transmission cooler, I would drain, refill and run it. at least 4 times. Then change the filter, then drain, refill and run another 4 times. Yes, it's a lot of fluid and effort, but you are only able to drain about 25% of the total fluid each time, so it's necessary in order to really replenish the system with clean fluid and fluid is cheap compared to a rebuilt box.

Then see if you have any improvements before making a decision.

Good luck

Paul

[Cossington]

Is the insulation etc all in place, around the gearbox? Just a thought before you have the gearbox removed and rebuilt.

I have a manual (conversion) and was surprised at the amount of transmission noise I was hearing. The cowling and insulation was either missing or not bolted into place, allowing far more noise into the cabin than should be. It has now been sorted, after some removal of parts of the power dash and the sound levels are far lower from the transmission - the purr of the engine is the noise I hear.

Good luck,
David

[BigCatXJS]

There doesn't seem to be much room in the transmission tunnel and I have the pleasure of (still!) trying to track-down a rattle when cornering hard. I suspect exhaust pipes banging against the transmission tunnel! I am running a getrag 265 in a '89 V12 HE coupe.

If you have already renewed the engine mounts and gearbox mount then you should have less movement and cause for transmission tunnel rattles than what I have.

Rich.