Here you can find information regarding repairs of the Mazda 4.0L 5R55E transmission. In this guide we
will cover
the basic componenets and repairs involving the transmision. This information includes
the draining of old transmission fluid, changing of the transmission filter, removal of the transmission oil
pan, as well as filling in new fluid. We also touch on the subject of removing the
transmission from the vehicle. For more detailed transmission information please see the transmission section on
the website and find your corresponding transmission. During the repairs we will include
certain procedures that should be followed when performing the work as well as the torque specs for the bolts
involved.
Transmission filter replacement
The first step involved in replacing the transmission filter is to drain out your old fluid from the
transmission. To do this you can either siphon the fluid out using the trans cooler lines
or you can let it all come out when you remove the pan. While the pan is pretty self explanatory the cooler is
not. Basically you can disconnect both of the trans cooling lines and run the engine while in park
and this will cause the transmission to pump out its fluid through the lines. Be sure to have a jug or container
ready if you do this as you could get more than a gallon out. Now you can begin drainging the fluid
from the troque converter. This can be done by removing the rubber plug from the bell housing and turning the
engine over until you see a bolt or plug. This plug will be a 7/16's and can be removed to drain the
converter. Once drained you can then reinsert the plug bolt and torque it to 15 ft-lbs. Regardless of whichever
way you choose
the next step is to jack up the vehicle and remove the pan if you have not already. Once the pan is off you can
now see and access the transmission filter, when removing be sure that the o-ring comes out with
the filter as if left in the trans this can become a major problem. Go ahead and install your new filter and
begin reassembling the pan back onto the transmission. The pan bolts should be torqued to 12 ft-lbs.
When reassembling the transmisson and engine you will need to tighten the engine flexplate back up to the
transmissions torque converter. This can be done through a small opening on the bottom
of the bell housing. Through the opening you can access the bolt holes and insert one at a time while moving the
engine to access the others. Occasionally you may need to adjust the torque converter before
connecting the flexplate in order for the bolts to line up. If everything is correct the bolts should screw
in easily with little to no resistance. These bolts should be torqued down to 35 ft-lbs to ensure none of them
loosen up when the engine is running otherwise you could end up with a major issue on your hands. Once all the
bolts have been installed and torqued you can turn over the engine to ensure it turns smoothly
and that there are no issues with the torque converter.
Mazda CX-9 Flexplate to Converter Torque Specs : 35 ft-lbs
The transmission pan transmission can be removed via a series of bolts that hold it onto the bottom of the
trans. To reinstall the pan you can use either the same gasket if
still in good condition or a new gasket and some silicon sealant to aid with it. Once the gasket is in place you
only need to replace the pan back up to the transmission and begin installing the bolts. These
bolts will need to be torqued to 12 ft-lbs to safely secure the pan to the transmission. Once all have been torqued
then the pan is properly in place.
Engine to Transmission Bell housing bolts
When connecting the engine and transmission back together you will need to install a series of bell housing
bolts to make sure that the two larger components stay securely together. On the 4.0L
engine there is usually 6 to 7 of these bolts that are spread out around the outside of the housing. Each bolt
should be installed and then torqued down to 35 ft-lbs. While torqueing the bolts down be sure to
check that nothing is wedged between the engine and trans and that the torque converter is in its proper place.
Bolting these together without everything being in place can cause damage to componenets and potentionally
your transmission seal.
Mazda CX-9 Bell Bolt Torque Specs : 35 ft-lbs
Drive Shaft Bolts installation
On the back of the transmission there is a connecting plate that is used to bolt the driveshaft to the
transmission. The bolts that are used to connect them should be torqued to 80 ft-lbs, if
desired you can also put a little bit of blue loctite on the bolts to ensure they do not come loose.