Changing the gearbox filter on my 2003 4.4 bmw zf boxed ffr shortly. I know from last time that the torque headed screws that hold the pan on need replacing. Anybody know what size bolts will do the job ?

i used ebay, and bought m6 stainless socket head bolts, 20mm long. these have a normal allen key head, as opposed to torx. some days I hate torx, others a don't mind so much. these should not be that tight, but I had mullered a few trying to get overtight bolts out, and had to resort to using a sharp chisel to knock a few loose. just make sure you spray the old ones, and that you are definitely using a t27 torx spline/key you can buy these individualy on ebay, again, for about £5 all bolts are undoable with an allen key, except the couple obstructed by the trans cradle bar. However, I would recommend you use the T27 mini spline socket, shaped like this, http://www.ebay.co.uk/itm/T27-TORX-KEY-BIT...uF62PtFXfA not necessarily this make, choose your trusted make, some of the bolts need a universal joint..

I hope you bought a gasket, as they are very hard to remove, without snapping. and its pointless trying to use sealant to bodge it together.
follow instructions to refill properly with fluid, and when warmed etc. using and old bottle, -count back in, whatever came out, and more if poss. I bought a cheap syringe. so easy to use, and no mess. http://www.ebay.co.uk/itm/Oil-Fluid-Suctio...SwGzlTxWh1

Last edited by johnboyairey on 5th Jan 2016 11:57pm. Edited 1 time in total

Cheers for that. Didn't want to go down the torxs route again.

i agree, make sure it's a T27, a T25 will fit, until you have a tight one and it'll slip and ruin the head.

I cannot understand the 'Torx revolution' they are terrible things and it is difficult sometimes to get the right size and do not get me on 'rounding off'.I struggled to get out several of mine,the hardest ones to get to as usual.Just took one to the local hardware supply and got hexagon head although I had to put 2 of the torx[or was it 3] back as there is a couple of narrow channels that the hex wouldn't go in.I did however repair the gasket with hoylamor without problem as I only bought 1 gasket and when I do another drain I can remove it again,clean then put on new gasket.

they're better for use with power tools on production lines - all about speed of assembly.

More generally;
Apart from being more compact they're a pretty terrible substitute for hex head machine screws.

On the other hand they're much better than slot head, Phillips/Pozidrive or Allen machine screws. All three of those have a tendency to strip easily and the slot/Phillips/Pozidrive cam out very easily. If you use the correct sized bit, torx screws are very strong - but as you say it's not always easy to choose/find the correct size - but to be fair you can't really blame the fitting for the user choosing the wrong size tool. It's only the same as someone using a metric spanner on an SAE nut and rounding it off in the process.

Iirc the Philips screws you mention were invented by Philips to speed up there production lines years ago .
Before that there was only slotted screws .

Torques are ok on most things .
As long as the right tool is used , inserted fully , and the screw or bolt is clean they come off no problem .
They've been using similar things to bolt cylinder heads on for years using much greater torque settings .
A little trick is to use torque socket drives and put the socket on an extension and give it a tap with a hammer before putting the ratchet or breaker bar on .

Quote:

Iirc the Philips screws you mention were invented by Philips to speed up there production lines years ago .
Before that there was only slotted screws .

I think so yes, it was to do with early powertools and 'stanley' push action screw drivers. They didn't have automatic torque limits so the were designed to cam out to stop the bit breaking or stripping threads if you tried over tightening them. It was an improvement over slot heads at the time.

With modern pre-set torque power tools Torx is far better - i think they came from the aviation industry.

Problem is someone gets there before you and uses the wrong bit.

Have never had a problem with screws,a pz2 or pz3 or ph2 or ph3 are almost exactly the right size and rarely a sloppy fit.Torx however seem to be different with so many different sizes,my friend lent me a very comprehensive set and I could not get an exact match ,either too slack or too tight,i ended up using the tight one and literallt had to hammer it on to get hold,which I ended up giving several a good hammer as I was loosening as they were very tight and feared stripping,then used the slack one when I had got them loose.!

Did the deed today... I challenge any one to do this over a piece of white carpet and not make a mess !! Luckily I had a garage with a ramp. Ditched the tork screws I took off and replaced with M6 16mm allen head screws and washers, stainless steel of course. Did the engine oil and filter as well. Of course this is a Range Rover so the engine management light which I haven't seen in two years came on as soon as I left the garage..... GIVE ME STRENGTH !!

Looks a bit rusty,i spent an hour or more sanding mine down and got some paint on it,looks great too !

Patenation...all the rage in the Antiques world.....

they don't rust, unless they DONT leak!

glad you got it sorted!


memories of fluid running up my wrists, and burning my hand trying to get the filler plug back in....

all is forgiven. im glad you used washers too, as I forgot to say that earlier.

the joys of ebay.. click..... wait........ ding-dong, 'sign here mate'.. -sorted!