Land Rover Repair: trans, wind chill factor, larry weaver

Question
Hello. I have 3 short questions about AUtomatic transmissions. (1). Can a transmission flush harm a transmission? (2). Why do no automatic transmissions have a drain plug like an engine? Only by changing the filter can a portion of the fluid be changed? (3). My car does not go into gear on cold mornings, why not? Thanks. Larry Weaver

Answer
Hello Larry,

1. If done properly, ATF flushes should never harm your tranny. According to my manual, ATF flushes should be performed by your LR dealer.  It is a complicated process and requires special attention. Some mechanics will say that disturbing the system can open the tranny to problems.  I've seen what happens when old fluid breaks done and the cost is horrific.  Have an expert perform this.
2. I've been told that ATF should always be free of any contaminants because the metal it protects must be surgically clean.  Finding metal filings are often found in the filter and sump area.  Its just a more thorough method of keeping the gears and clutches contaminant free.
If you are going to the trouble of changing the fluid, why not change the filter?  I have heard of reverse flushings...I think the fluid is sucked up by a special machine that then injects fresh fluid (a Porsche owner told me of this method).
3. I live in the Laurentians mts of Quebec.  During the winter months, temps can go as low as -35 F and even colder with the wind chill factor (WCF).  It is not uncommon for fluids to thicken with exposed to such extreme temps.  You may want to install a block heater to help with this.  I have also come to the conclusion that LR is not made for cold climates.  Its a 'cold-blooded' machine and as soon as winter sets in, everything starts to freeze:  doors, windows, locks, trannies, engine, everything!  You'll just have to pamper your LR and keep it in a garage.  If not, use block heaters, insulated engine and battery wraps and whatever you can think of the combat this common problem.  
I don't have a garage (yet) but wish I could keep my Disco warmer.  Its the WCF that does the most freezing.

To change your ATF:  there is a nut in the underneath of the sump pan for draining. Since you're down there, you should also do the transfer box. This also contains ATF and is likely to be needed too. The filler is on the back towards the passenger side and the drain is somewhere nearby, I can't remember exactly. Bear in mind that the boxes hold quite a lot of ATF between them (more than 5 litres).  Gearbox is easier to flush than tranny.  I own a 5 speed manual tranny and the process is very different.  Easier for manual than automatic.

Hope this helps,

JohnMc