I have a 2003 2500 5.7 4x4.. I am going to change transmission fluid.I already have filters and atf+4..My question is do I need a Gasket? The Dumb A@#$ at parts store said no..I'm not the sharpest tool in the shed but seems to me I'm going to need one..Can someone clear this up for me.. Thanks

 

Im pretty sure its ok to use RTV, the 2004 FSM states the following (its the one I have handy):

CLEANING
(1) Using a suitable solvent, clean pan and magnet.
(2) Using a suitable gasket scraper, clean original
sealing material from surface of transmission case
and the transmission pan.

INSTALLATION
CAUTION: The primary oil filter seal MUST be fully
installed flush against the oil pump body. DO NOT
install the seal onto the filter neck and attempt to
install the filter and seal as an assembly. Damage to
the transmission will result.
(1) Install a new primary oil filter seal in the oil
pump inlet bore. Seat the seal in the bore with the
butt end of a hammer, or other suitable tool.
(2) Place replacement filter in position on valve
body and into the oil pump.
(3) Install screw to hold filter to valve body (Fig.
67). Tighten screw to 4.5 N·m (40 in. lbs.) torque.
(4) Install new cooler return filter onto the transmission,
if necessary. Torque the filter to 14.12 N·m
(125 in.lbs.).
(5) Place bead of Mopart RTV sealant onto the
transmission case sealing surface.
(6) Place pan in position on transmission.
(7) Install bolts to hold pan to transmission.
Tighten bolts to 11.8 N·m (105 in. lbs.) torque.
(8) Lower vehicle and fill transmission with
Mopart ATF +4.

 

Thanks for the info.. I'll have to get some RTV so I can get this done..

 

I got the gasket. It was just a few dollars more than the tube of RTV. I'd pay $2-3 more for less mess. I also only got a 1500 rwd only. still the same 2003 5.7L motor tho. Basically it just comes down to your decision. Do you feel like using RTV when there is a gasket available?

 

Good point. One more question how do I know what transmission I have? I asked the guy and he looked at me kinda funny.Than said he didn't know either..

 

Build sheet.

 

Where do I find that at? When I bought this truck it didn't come with anything in it just a title

 

you got the 4x4, so my best guess is the second one...think there are only 2 different ones for the 5.7 hemi and i got the first, so you must have the second. I took a lucky guess at the parts store. Mine was basic 2wd so i chose the first of the two choices.

 

Yea what I quoted above was for the 45RFE (4-speed)/545RFE (5-speed)..

The basic 4-speed 48RE calls for a gasket...
(7) While holding pan level, lower pan and gasket
away from transmission.
(8) Pour remaining fluid in pan into drain pan.
(9) Remove screws holding filter to valve body
(Fig. 90).
(10) Separate filter from valve body and pour fluid
in filter into drain pan.
(11) Dispose of used trans fluid and filter properly.
INSTALLATION
(1) Position a new transmission oil filter onto the
valve body.
(2) Install the screws to hold the filter to the valve
body. Tighten the screws to 4 N·m (35 in.lbs.).
(3) Clean the gasket surfaces of the transmission
oil pan and transmission pan rail.
NOTE: The transmission pan oil gasket is reusable.
Inspect the sealing surfaces of the gasket. If the
sealing ribs on both surfaces appear to be in good
condition, clean the gasket of any foreign material
and reinstall.
(4) Position the oil pan gasket onto the oil pan.
(5) Position the oil pan and gasket onto the transmission
and install several bolts to hold the pan and
gasket to the transmission.


Im too lazy to post the diagrams, but the 48RE is pretty easy to identify as the pan is perpendicular to the transmission (long ways)

Whereas the 45RFE and 545RFE both have pans that run parallel to the transmission..

Also on the two above it says there is a label on the drivers side of the transmission just above the pan..hope this helps


Again just going by my 2004 1500 FSM...Im sure there are differences that I dont know about.

 

From the factory there are no gaskets on the trans pan or diff cover. All RTV. A gasket came with my aftermarket trans pan (cast aluminum) so I used it.