A relative gave me an 86 Dodge Ramcharger,318 powered, auto, limited slip, with a snowplow. He wasnt one for maintenance however the truck still runs great. The tranny fluid cooler on this truck is not connected to the radiator. It has its own seperate cooler alltogether that is mounted in front of the radiator and yes this is stock configuration. As far as i know the tranny fluid has never been changed but it has had various amounts of make up fluid added to it. After i plowed snow for 2 days i checked the fluid. Yup it smelled old and oxidized and was dark. It was not burnt or gritty. I have read that you do not change fluid on a tranny that has never had this done before. Well this truck sat for 2 years and i couldnt resist. I put a hose down the tube and removed 5 quarts of fluid. Replaced the fluid and it runs fine. I will monitor the fluid color as i expect the new fluid will remove varnish and clean up the valve body in general. When the fluid color changes, I will drop the pan and change the filter and fluid. I have read posts on this site that contradict each other. At 150,000 miles this tranny and engine should have been toast. Well it still runs strong and burns no oil. Tranny shifts good and does not slip. So did i do a bad thing when i changed out half of the tranny fluid? I guess the stock tranny fluid cooler works well enough that i do not need to add another one. If i change the diff fluid what are the chances that i will have leaks or the limited slip will shoot craps? Or should i leave it alone even though it is black and stinky. I read lots of stuff on this site and sometimes i think it is overkill. This truck is bone stock but it has the right stuff for what i use it for. Now there is the problem i had with my 92 cummins powered Dodge 1 ton. Broke the carrier on the spicer 70 but that is another story..............
150,000 miles on a Mopar 727 tranny
- Thread starter greasezerk
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Zerk:
The external transmission cooler on this vehicle may have been its saving grace. I've heard that you don't want to flush a higher mileage transmission that has never had a fluid change, but I don't think just changing the fluid is necessarily a bad thing. And the five quarts or so that you changed is probably only about 30-40% of the total volume of the system, anyway. I think your plan to drop the pan and change the filter and fluid again once the color changes is a good one.
The external transmission cooler on this vehicle may have been its saving grace. I've heard that you don't want to flush a higher mileage transmission that has never had a fluid change, but I don't think just changing the fluid is necessarily a bad thing. And the five quarts or so that you changed is probably only about 30-40% of the total volume of the system, anyway. I think your plan to drop the pan and change the filter and fluid again once the color changes is a good one.
I have had previous experience with that exact tranny, just a few years older. My truck was an `80 360/lockup 727. It only had 120K on it, but I knew it had problems when I purchased it. I know that the previous owner hadnt done much when he was proud that he had changed the upper radiator hose all by himself.
Anyway, once the truck was in my possesion I pulled the pan and replaced the pans contents and the trans filter. There is a round magnent in there that catches some of the stray particles as well, mine was a large bump of goo. After that mini service the truck still ran great. It started seeing duty as a daily driver and a lift kit and 35s were fitted without changing the gearing (2.96:1). I believe that is what finally killed mine, not the change of the fluid.
The way I see it, new fluid that lubricates is better then old gritty fluid that doesnt. IMHO, most people say that new fluid in an old trans will clean the internal parts and cause leaks. How hard it is change some seals anyway? Id much rather do that then drop the whole trans (done it to said vehicle when the trans was rebuilt).
Just my .02¢
-Jon
Anyway, once the truck was in my possesion I pulled the pan and replaced the pans contents and the trans filter. There is a round magnent in there that catches some of the stray particles as well, mine was a large bump of goo. After that mini service the truck still ran great. It started seeing duty as a daily driver and a lift kit and 35s were fitted without changing the gearing (2.96:1). I believe that is what finally killed mine, not the change of the fluid.
The way I see it, new fluid that lubricates is better then old gritty fluid that doesnt. IMHO, most people say that new fluid in an old trans will clean the internal parts and cause leaks. How hard it is change some seals anyway? Id much rather do that then drop the whole trans (done it to said vehicle when the trans was rebuilt).
Just my .02¢
-Jon
greasezerk
An Auto-Rx cleaning of that transmission and then a complete flush would add life to it.
Ken
An Auto-Rx cleaning of that transmission and then a complete flush would add life to it.
Ken
Seems like alot of problems occur after a trans flush probably several partial flushs may slowly clean out the crud instead of all at once. It's my theory on the problem .727 transmissions are supposed to be pretty heavy duty compared to the crap made these days.
I've always rolled the dice in favor of fresh fluid.
IMO: get the vehicle to op-temp, drain convertor (plug on torque convertor under external tin cover); pull and clean pan with new internal filter & reuseable MOPAR pan gasket; (install Trans-Go RV/HD Shift Kit); adjust bands; add Magnefine external filter after auxiliary cooler (I prefer the external cooler be plumbed after radiator cooler; per factory -- both operating); run 6-ozs of ARX with Dexron-Mercon (cheap).
See other posts (mech section) for flushig trans via return line to trans from cooler at about 3-4000 miles or 6-months, IMO, (very easy to do, actually); add new Magnefine filter, SCHAEFFERS #204s D-M and go at least a year.
I have yet to take an old vehicle and not get close to 200k out of an oem trans via above (similar; different filters and fluids).
Have had a few 727's; have one out back that was resealed after sitting about 5-years; is now over 30-years in service. (Front pump seal is leaking again, though; common on 727). 135k.
I'd rather have the trans die quickly than on a trip 300 miles from home.
IMO: get the vehicle to op-temp, drain convertor (plug on torque convertor under external tin cover); pull and clean pan with new internal filter & reuseable MOPAR pan gasket; (install Trans-Go RV/HD Shift Kit); adjust bands; add Magnefine external filter after auxiliary cooler (I prefer the external cooler be plumbed after radiator cooler; per factory -- both operating); run 6-ozs of ARX with Dexron-Mercon (cheap).
See other posts (mech section) for flushig trans via return line to trans from cooler at about 3-4000 miles or 6-months, IMO, (very easy to do, actually); add new Magnefine filter, SCHAEFFERS #204s D-M and go at least a year.
I have yet to take an old vehicle and not get close to 200k out of an oem trans via above (similar; different filters and fluids).
Have had a few 727's; have one out back that was resealed after sitting about 5-years; is now over 30-years in service. (Front pump seal is leaking again, though; common on 727). 135k.
I'd rather have the trans die quickly than on a trip 300 miles from home.
I would add 6oz of auto-rx and follow the directions for application. I would definately get it flushed after the application is done at a trany shop. THe auto-rx will help re-condition the seals as it gentley cleans! IT is not harsh like most transmission treatments!
The home flushing method works fine as well so long as you have an extra set of hands to help!
[ January 01, 2004, 05:57 PM: Message edited by: JohnBrowning ]
The home flushing method works fine as well so long as you have an extra set of hands to help!
[ January 01, 2004, 05:57 PM: Message edited by: JohnBrowning ]
No leaks and the tranny runs and shifts great. Dont think i will add any ARX or get ir flushed at a shop. I think that will just cause trouble. I will just change out the fluid and filter when the fluid looks like it is ready. If the tranny was shifting hard or funny then i might use ARX but all seems to be well so dont fix what doesnt need fixin.
MolaKule
Staff member
Question:
Why was makeup fluid added, Did it leak? This may also have been it's saving grace; the add package was bumped a few times if this were the case.
My point was that my relative is not the type of person who would change the tranny fluid and filter at x amount of miles. Over the span of time he owned the vehicle if it leaked fluid he would just add fluid and keep on going until he HAD to get the problem fixed ie tranny,valve cover gaskets, ps pump etc. This truck always seemed to leak oil. I traced down an oil leak to the oil pressure sending unit,it was leaking from the top. Replaced the unit and no more burning oil smell. Went to the car wash and blew off the thick crud that had built up on the manifold,front drive shaft etc. Heck i replaced the front driveshaft u joint in less than 5 minutes. It had so much oil dropping on it that the cups never had any rust build up aroung them. I put the yoke in a vise and with a few taps the cups came out real easy. Never got any u joint cups out that easy before. The tranny system has probably leaked and sure fluid was replaced yes that helped keep it going. lets just say that im surprized that no major component needs to be replaced. Im just going to keep it going and using it in the winter for snow removal then back to the farm for summer storage.
MolaKule
Staff member
Had an old 5-ton Dodge flatbed one time that we used for snow removal when we weren't hauling grain, but it had a manual tranny and we simply fed it a quart of 75W90 each time we made a run, since we never seemed to have time to replace the seals and gaskets.
My neighbor actually used it one time to dig a shallow pond.
My neighbor actually used it one time to dig a shallow pond.
I have been using the truck and the fluid looks like new. No color change. It does have a funky, old oxidized smell to it now. It got that smell after i worked the truck pretty good plowing slush and ice for around 4 hours. I guess the new fluid is cleaning up the tranny in general.
My understanding is that the 727 is one tough transmission and not typical of what is being produced today ... probably the reason its still going.
Below is a short synopsis of my understanding of old transmission fluid and what happens when you change it.
As you stated ... rule of thumb is never to change the fluid on a transmissin that has gone that long without prior routine maintenance ... they tend to die within ~3000 miles of the fluid change (typically).
Why not? Because the new fluid begins to clean up/suspend a lot of the previous deposits allowing path ways of escape(pressure leaks) not readily available prior to the fluid change (decade old fluid is usually thick and doesn't flow well). These pathways (pressure leaks) tend to develope over time from the chemical reactions found between very old fluid seals, o-rings, & aluminum valve body pasages. When the pressure drops sufficiently, clutch plates and bands begin to slip causing failure and the need to rebuild.
Please feel free to make corrections to above statements if you know them to be in error. Note that pressure loss can be attributed to fluid flow around an o-ring, a gasket, or through porosity in a valve body passage.
Below is a short synopsis of my understanding of old transmission fluid and what happens when you change it.
As you stated ... rule of thumb is never to change the fluid on a transmissin that has gone that long without prior routine maintenance ... they tend to die within ~3000 miles of the fluid change (typically).
Why not? Because the new fluid begins to clean up/suspend a lot of the previous deposits allowing path ways of escape(pressure leaks) not readily available prior to the fluid change (decade old fluid is usually thick and doesn't flow well). These pathways (pressure leaks) tend to develope over time from the chemical reactions found between very old fluid seals, o-rings, & aluminum valve body pasages. When the pressure drops sufficiently, clutch plates and bands begin to slip causing failure and the need to rebuild.
Please feel free to make corrections to above statements if you know them to be in error. Note that pressure loss can be attributed to fluid flow around an o-ring, a gasket, or through porosity in a valve body passage.
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