Finally got to doing this today. Planned to put Redline MT-90 in trans, 75W90 in diff (the one with friction modifiers for LSD). Got one of those on/off tube thingies at Pep Boys. Put the car on ramps (my driveway slants just right so that if one end of the car is on ramps, the car will be level. With the rear "up" I have good access to the diff, with the front up, I have enough room to wiggle in to get at the trans.

However, I could not for the life of me position the bottle + tube contraption so that oil would pour into the diff. Boo... The tube was quite short (about 10 inches?), and all the suspention and exhaust components are in the way. I will have to get a longer tube and repeat the experiment. Fortunately I tested "flow" before I opened the drain plug.. Otherwise I would have been quite f**ked.. Anyway,

The trans was a little easier. There is not much room under the car in this position, but by cutting the tub even shorter (about 5 inches), and using a poland spring bottle (it is a tad thinner than normal soda bottles), I got a contraption that would actually stay wedged between the transmission and floor of the car. So all I had to do was fill the bottle, crawl under the car, insert the tube, then crawl back out and wait 5 minutes. Rinse, repeat (figuratively speaking, of course.

I also bought a siphon pump (useless for oil, way too thick, even if heated up), and a syringe (also useless, the thing was so poorly made it took way too much force to move it... I could do it, but if I pictured trying to do this on my back, trying to get the liquid to go into the tiny fill hole.. no thank you).

Impressions? The shifting is great! Before it felt notchy and sticky, and now it's smoooooth. I would like to draw a very graphic metaphor involving Astroglide, but I am afraid that might get me banned :-D

As always, thanks to the members of the forum for the great tips. Couldn't have done it without you. I think this job would have been alot easier with the car up on decent stands / a lift, but I don't even have a level driveway, much less access to a shop.

 

Pour the tranny fluid in through shifter....much easier!

 

Enough to make you smile.

 

Lol that's a nice one. Certainly less effort than crawling around under the car refilling little bottles. Anyone got an easy way to do the diff?

 

Over the rear tire. I'm assuming when pouring through the shifter you're still leaving the "fill" plug open so that you don't overfill. Just wanted that to be clear for all.

 

Got some RP gear oil from NAPA yesterday... asked if they had a pump that could be used..... "Nope, its just a pain in the *** to do." Ugh. I got some 1/2OD clear tubing from Home depot and a funnel to fit, sure not fast but its working.

First time I have changed the diff fluid, that magnet was caked, @ 15K miles. I have changed the tranny before so it wasnt so bad. Only changing it again cause I was hard on the tranny this winter getting up my hill.

 

if all else fails in attemping to replace the tranny and rear diff...take your fluids to any jiffy lube and they can do it for you...i work there and i do it all the time..peace of cake..fyi they take the old fluids also no disposal fee

 

Just did this yesterday with Mobil 1 (SAE 75W-90 GL-5).

Transmission took 2L - maybe because i used some the new oil to run through it... clean and reused original crush washers, no leaking. Differential took 1.5L did the same. Result, like everyone else... much smoother ;-)

 

Just to add a data point on RP oil, my experience has been pretty negative. I was on factory oil for two winters and one summer, including a half dozen track events. This spring, I did two track events, then changed the trans and diff oil over to RP Max Gear 75W90. Shifting felt exactly the same on the street, but at the first track event, after about 10 minutes of running hard, it started grinding everytime I went into fourth. Yesterday, I ran another track event and got the same grinding. I suspect the RP oil gets very thin at high temperatures. I'm going to buy something else (Mobil, probably) and change again this weekend.

 

Wow... that's exactly what's happening to me, in fifth and second. I was thinking it could be the oil but now I've my doubts. I'll make an oil change next week and see...

 

I also got my supplies at NAPA, including a marine pump for about $15. It is designed for syphoning fuel out of the tank, but it pumps gear oil just fine as long as it is not the middle of winter. If you live in an area where people own boats, they should have a marine section.

 

Just Finished my oil treatment too? Things go alot quicker if you have a friend help too? Shift is very smooth again.....sweet! thansk to all for the information to get this done! Not paying Mazda $180 for it!

 

where do you find a socket this size? i went to advanced auto parts and they didn't have any bigger than a 22mm?

 

Try Sears. Their web site shows a half inch drive 5-piece set 22 mm to 26 mm, list $30. 12 point.

Bet Snap-On has these sizes, but if you can afford Snap-On you can afford to pay a master mechanic to do it for you.

Ken

 

Snap-On sells very high quality stuff

but I got mine at Pepboys.

 

Got mine from sears. The set of 5 12-point sockets that ken-rx8 metioned... Worked just fine for me.

 

Can anyone tell me which direction to unbolt both the differential and transmission bolts? If you are on your back and looking at the differential chamber, am I cranking clockwise/counterclockwise to unbolt it? I tried to use just my muscle and that didn't budge it from either direction. Only thing to consider is getting an impact wrench and wacking it with a rubber mallet. But, before making things worse, which direction to loosen this? Photos with directional arrows would be nice

 

Righty tighty, lefty loosey.

 

Hmm, this looks quite easy. Only thing to be unsure about is where to dispose of the used oil, and the correct torque (only have a cheap torque-wrench).

 

In the US, most auto parts stores will accept used motor oil for recycling. Not sure about Norway. Also, check with local auto repair shops that change oil. They may accept your used oil.

Torque specs from the shop manual:
27-48 Nm (2.8-4.9 kgf/m, 20-35 ft-lbs)

Best to replace the washers as appropriate when you reinstall the drain and fill plugs.

 

Thanks Renesis!!

Should I be concerned about taking a mallet to the wrench and pound the crap out of it?

 

it shouldnt be that tight. make sure you are unscrewing the right one. a friend of mine was unscrewing something else before i noticed!

and - righty tighty, lefty loosey as noted above.

 

That's why I like ratchets.. You can test it in the normal orientation to make sure you're tightening or loosening as appropriate, then once you put it over the bolt it doesn't matter if you are upside down on your back or whatever..

Mine were on a lot tighter than the torque spec.. I guess the same gorilla that worked on the oil filter got to these too..

 

So when you went to the Mazda dealer, what did you ask for (noob question), were you like " i need some crush washers for my tranny" or??? cus im a little confused, are the crush washer sizes different?

 

I've heard them referred to as crush washers or gaskets. You need the ones for the drain plugs on the diff and trans (the fill plug ones you can reuse most of the time). IIRC there were part numbers posted earlier in this thread also...