Quoting: Titsy
Any suggestions on how to purge and flush the box lines and cooler?
I'm thinking disconnect the cooler oil lines as close to the box as possible, then connect up the feed line to an airline ( compressor ) and blow all the oil out into a container. When I change the gearbox oil I use one of those large plastic under bed storage boxes on wheels ( cost £8 but you can borrow mine it you want )
Blow all the oil out into the "clean container" until you have a good flow of air back through the lines.
Now if you have a contamination problem it should be visible in the flushed oil, if the oil is a nice ruby red colour and clean that crosses the cooler and oil off the problem list.
It also saves you dropping the gearbox sump coz it's messy and costs a few quid in oil.
If there is a contamination problem, you'll have to drop the sump, change the oil and filter, run it again for a few miles and repeat the process.
The only way to check the filter for contamination is to break it apart once it's out
If you do buy the filter set make sure that you order the cork pan gasket ( the standard filter & gasket GM part No. 24200796 - £47.54 is paper and is a b!tch to seal )
The cork sump gasket is only £3.77 from USless Automotive
Another key point , the sump bolts should only be tighted to 8lb ft which is bearly more than finger tight
I had a slight oil leak last month and just went round and nipped up the bolts just 2 flats more - sorted !
I've done the oil change five times and it's messy, the first time I left the gearbox draining for two days and it was still dripping !
If you need a hand give me a shout
