Draining trans fluid

[transe]

Sorry for getting off topic, but I've been contemplating this for some time now. Why do the newer transmissions have such a longer service interval than the older 47/48RE? I'm guessing a lot of it has to do with today's fluids compared to what was available 15 yrs ago with my 47 but is there more to it? Since the ATF4 is all that is available is it safe to extend service intervals past 30k miles or does the internals or the design of the 47 still require the shorter service intervals?

Yes, ATF+4® (officially it is MS-9602 fluid) is a significant improvement over the old ATF+3 (MS-7176) fluid. I believe that is the primary enabler behind the extended drain intervals. If you are running ATF+4® fluid, I'd think you could reasonably extend your fluid change intervals, although I'd be a little hesitant to double them. Check the fluid condition occasionally (pull the dipstick and see if the fluid is still red, and doesn't smell burned), and if it's OK I might go 45K miles on it.

 

[JR]

Thank you for your input. The trans that is in my truck is actually out of my former 00 which I retired due to rust issues. It was built by a friend that is well known in the tri state area for building high horsepower truck pulling transmissions and he told me all I needed to run in it is the cheaper GM spec fluid. I ran it for the initial flush but went back to the better ATF4. I recently did a flush at 35k miles and the fluid still looked great. Slightly darker in appearance but still had the same feel and smell as new fluid. Thanks again.

 

[Cummins12V98]

Cummins, did you see a drop in temps? I got both r/e and transmission pans before I checked the temps. neither needs them but if I sell them , I loose money. I figure WTH, go ahead and put them on. .



I have never seen the trans go over 205 and the r/e 185.

I changed the pan and to AMZ/OIL in the trans before I really did any serious towing.



I can tell you towing up 6% grades and flat ground that the temp ranged from 180 to 185 at 90 outside.



I would attribute the cool temps to The MagHytec and the AMZ/OIL.

 

[cerberusiam]

There is no magic oil that will lower transmission temps. Heat is a function mechanical friction and fluid coupling. All the transmission fluids are close enough in formulation they will not be an appreciable difference. If there is something in the trans is going to give up.

No trans pan is going to make things run cooler either, just delay the time it takes to get to temp. A 2 quart add is not going to make a difference in maximum temp under a load. Unloaded it migh show some small difference but that is not what the truck is normally used for.

The biggest reason to change the fluid on the reccomended intervals is the volatile additives that cook out over time. All the group 3 and group fluids are really good at what they do because of these additives. The downside is they are volatile when heat is applied. The other almost important reason is the amount of friction and steel material the fluid suspends. Its grit and that will never be good on the internals. The RE's in these trucks make metal and chew the frictions up constantly, its one of annoying traits of the 727 based units. There are fixes for it but requires some precise maching and\or parts to address that.

Using the truck hard and comparing 30k fluid with new, the difference is obvious. You have to look at it side by side to see if a change is warranted.

 

[Cummins12V98]

Well how do you explain my temps running cooler than the rest of the posts?

 

[Cummins12V98]

I just looked thru some photos of my instrument cluster. I-10 east to Pheonix 154 at 71 outside in 6th, to pahrump May Madness 163 outside 94 also 188 at 100.

That is the most I have seen towing. In Palm Springs stop and go for miles it was 230 or so.

 

[cerberusiam]

Well how do you explain my temps running cooler than the rest of the posts?

Don't see any comparisons that say that is true or false. Trying to compare temps across trucks, driving styles, and loads when none are known is meaningless.

 

[JR]

I am no expert by any means, but I do try to educate myself on my vehicles and whatever parts/fluids etc I may use on them. In looking at the group III stocks, and the shear stable viscosity improver developed by Lubrizol, the ATF+4 is a very capable fluid. When comparing ATF+4 to other OEM fluids it far exceeds all others in viscosity and shear tests, by as much as 40% . I have seen Amsoils tests and comparisons to the ATF+4 and the only real advantage I could see would be extended service intervals.
This is just my humble opinion from researching, I am by no means an expert on any of this.

 

[Austin Diesel]

Did as specified and it all went well

found out that special permatex AT RTV sealer goes on pan rail # 81180 also

blogged my procedures on another thread within this site tonight went well minimal mess clean trans fluid once again

Austin diesel

 

[Austin Diesel]

2008 6.7 Auto LWB, 2WD 86,000 miles

Heres how it went:

Layed some black bisqueen plastic sheeting on drive under pan area after safetly blocking up chassis, Removed lower drain line bell housing bracket bolt, drivers side, removed fitting from side of trans,
tight fit because of exhaust pipe but it did come out of there, lines are rigid, worked bellhousing clamp a little and it loosened up with penetrating oil ,and fitting came out ,used 1/2" pipe plug with teflon tape to plug on lower input return line on side on housing ,
hooked up 5/8" heater hose to lower fitting tightened hose onto fitting with hose clamp as it kept coming off, started, put in neutral over 5 gal bucket drained fluid briefly shutdown motor,
Loosened pan bolts, hit side of pan with dead blow mallet came loose,Dropped corner of the pan ,Drained into catch basin, found magnet needed cleaning, would add another small magnet to a proper location also,pan needed cleaning,carbon and fluid burned,rinsed pan out for particulates,removed old pan rail silicone with a wire wheel, there is no pan gasket on a 08 2wd,
requires special "Permatex" or Dodge Auto Trans RTV gasket maker, RTV #81180 (Advance Auto) required for +4 Fluids removed and reinstalled new o ring seal for pan filter in cast housing as per directions,tapped in with a socket and extension ,let drain for a while ,replaced 2 trans filters, return cooler filter and felt pan filter,wiped all pan rails with acetone several times and right before filter and pan installation,cleaned pan bolts with wire wheel,rinsed with brake cleaner,
Do not overuse silicone sealer, nice even bead all around pan rail cleaned out bolt holes on pan of excess too much will fill pan rail bolt holes and could caused pulled threads in housing,

installed hand tight evenly ,then torked to 105 inch pounds let RTV set up for hour checked tork :OK curing overnight hopeing for 0 leaks later,

add 5 quarts to pan, start, put in neutral quickly,pump old burnt fluid into bucket, add fluid quickly or shut down and refill pan repeat till fluid clears, remove plug from housing ,replace hose fitting to housing, fill as needed ,restart i bought 19 qts said it holds 17 qts +4 ATF , replace bell housing tubing retainer bracket bolt test drive after running through functions in driveway recheck fluid levels add as needed,

From Genos:

Mopar #83443 pan filter

Mopar #04799662AC return cooling filter

or Pioneer # 745215 or
FK-331 power torque return filter

Permatex # 81180 Auto Trans RTV Gasket Maker/ Advance Auto/ Napa

And i was going to let a shop have all this fun but its right and flushed and clean again,

Austin Diesel