Dodge A500 Transmission / How often to service ?

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I have a 1990 Dodge Dakota with the 3.9 and A500 transmission and was wanting to know how often to service it. The owners manual seems a bit excessive.
 
The ATF+2/ 7176 fluid available in 1990 was not really very durable. Modern ATF+4 is much much better and backwards compatible, in fact one can no onger get ATF+2 or +3.

Just do not use anything but ATF+4

I added a drain plug to my a-500 transmission pan, and recently a remote transmission filter.

Keep the tx cool with an addtional tx cooler plumbed after the radiator cooler. The rear line on the TX is the return line.

I go 25k miles before dropping and replacing 4 to 5 quarts of ATF+4 of the ~12 quart capacity. The in pan filter/rock catcher should be replaced regularly and the magnet in the pan cleaned of ferrous sludge. Not sure the mileage on that.
 
It came with a cooler installed when I got it. For some reason the manual lists the fluid to be changed every 18k. I tow a lot with it and it seems to be making more heat than the cooler can get rid of.
 
Originally Posted By: Justin94
It came with a cooler installed when I got it. For some reason the manual lists the fluid to be changed every 18k. I tow a lot with it and it seems to be making more heat than the cooler can get rid of.


That is a very subjective doesnt not contain much useful information.

What Transmission temperatures are you seeing? And from where?(pan etc)
 
Not sure on temps , but you can smell the trans getting hot after pulling a long hill. As far as towing , I tow between 6-8k.
 
I hope you are keeping it from engagng overdrive aon anything but 55+ flat land freeway, [perhaps not even then.

Also sounds like you need a larger and or more efficient additional tx cooler. I'd be changing the fluid frequently towing that much with a light duty transmission that smells hot after a pull.
 
I keep the o/d off when towing. It was connections for a second cooler. Highly thinking about adding a second one. One other thing I'm wondering is why does the engine not attempt to overheat when towing double the rated capacity ?
 
Do you have an engine oil temp sensor? I do not really trust my coolant temp gauge very much.

Of the three types of additional coolers, the most common type is the fin and tube cooler and is much less efficient than the stacked plate cooler.

I have a fin and tube, and not a very big one at that. I will upgrade but i would like to have some data for the before and of course after.

http://transmissionrepairguy.com/transmission-cooler/
 
I do not have a oil temp sensor. The coolant temp gauge is mechanical. And it has a fin and tube cooler that covers 1/4 of the condenser. Water temp doesn't exceed 215 F.
 
I would get the biggest cooler you can fit in there and keep to the "excessive" fluid swap schedule. The a500 (based off 904) is just not that strong of a transmission. They may be fine if you stick to the limits in the book but your clearly towing past those limits.

In my 91 I burned up 2 a904s before I swapped in a 727.
1st was the stock a998 with lockup. Died almost immediately when I started towing.
2nd one was a non-lockup 904. upgreded to low gear set,5clutch a500 front drum and pump. Good frictions. TransGo kit. Big plat and fin cooler.. Lasted about 20K. Smoked the front clutches.

The 727 is nothing fancy. "HD" 4 pin planetary's front and back. Has lasted over a decade pulling around 7K.
 
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Frankly I am surprised you can tow that much weight with the 3.9 and the A-500 without the transmission impersonating the bottom of the Fukushima reactors. I've never really towed anything with my full size van with the 5.2 and the A-500, but I did have to have the Tx rebuilt at 130K miles, shortly after my acquisition of it. It was apparently used to tow a boat from Florida to NY once a year. It had a trailer brake controller, and had no additional cooler installed. No idea if the previous owner kept it out of overdrive when towing, but it runs over 3000 rpm at 65 without OD and 2200 at 65 with OD and lockup.

That TX rebuild cost nearly as much as the Van did, and I've been trying to insure that it does not fail prematurely. I wish I had a stacked plate cooler instead of a fin and tube cooler, and I wish I had actual data on temperatures it achieves. If it regularly flirted with 220f plus I would likely first try the stacked plate cooler, and if that did not significantly lower temps I would add a powerful fan to it. There are all sorts of TX life vs ATF temperature data all over the web. In your usage I would be ensuring maximum cooling potential.

Plus one on the 'excessive' fluid refreshing schedule. They do sell deeper pans with finned heatsinks and a drain plug. I was not willing to lose any ground clearance for a deeper pan.

I recently replaced my steel lines and added the derale external filter mount, and it wound up requiring close to 7 quarts of new ATF. There was a noticeable difference in shifting, being faster and firmer, but especially the 2 3 upshift. The old fluid was still red, not quite pink, and smelled sweet, not burnt at all.

I am awaiting a deal on ATF+4 and will drain 4 quarts through the plug and replace with fresh as I want to make this vehicle last as I do not care about status or latest and greatest or the opinions of those who looks at a near 30 year old van and think what they are programmed to think.
 
Engine wise you can't tell the weight is back there , however trans wise you can once you start going up hill. I'm surprised the trans didn't let go. Previous owner serviced it around 15k ago with Napa Dex/Merc atf. The truck was a grocery getter before I got it. It had never towed anything.
 
Also make sure you adjust the bands as per the service manual. All TorqueFlite based transmissions require this.

My '96 Grand Cherokee 4.0 still has the original A500 (by then called a 42RE) with 257K miles on it.

Andrew S.
 
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Towing twice the rated load and the wrong ATF in a transmission which is notorious for grenading with the wrong ATF in it.

I feel sorry for it.
 
I got the truck about 4 months ago. It sat in a field for 20 yrs. The Napa fluid has been in it since 99. It only has 88k original miles on it.
 
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