So, I've been wanting to change the fluid in my transmission ('95 E40D)but I have also seen quite a few posts regarding transmission death immediately following a fluid change.

I picked this truck up 3 months ago with 79,900 miles on it, and after adding roughly 600 miles (some steep towing) it doesn't seem to have any significant transmission problems. It does downshift hard occasionally when getting on it but otherwise seems solid.

I would be changing ALL of the fluid (Torque Converter, Trans, Cooling lines) and adding a trans oil cooler all at the same time. Planning on running Valvoline Max Life ATF.


So that's how it sits now: 80,500 miles on the clock, last fluid change or history unknown.

So what do you think? 50/50 chance of killing this thing by changing the fluid?

 

Its a tough decision to make. It took me a year to get the guts to do mine. If finally started slipping and stalling in reverse, so I went ahead and changed it @ 192k miles. Last change unknown. The fluid was BLACK. I have since put almost 4k miles on it with no issues. Might have gotten lucky. How does the fluid look now? Is it dark and burnt?

I used the Valvoline Max Life ATF. Seemed to work for me and it was the cheapest fluid around here. I might also suggest an external transmission filter. I added one that uses a Motorcraft FL-1A filter just like the engine oil filter. I tried one of those in-line Magnefine filter's and it failed in less than 500 miles.

Here is my current filter setup:

 

The fluid looks good and smells fine right now.

I'm still undecided on the external filter, I don't want to overwork the pump by adding too much additional distance to travel. I was even skeptical about adding the aux cooler.

 

Isn't flushing the transmission usually the culprit, not draining and refilling? That's what the old timers usually tell me, anyways.

 

Service the transmission and enjoy the peace of mind.

 

I always get the transmissions flushed on used vehicles that I purchase.

IMO (and also that of the transmission shop guys), flushing the transmission will not kill a transmission.

If a tranny is good, it is good.

If a tranny is bad, it is bad.

Flush it, change the filter, add the cooler, add a temp gauge, and enjoy your truck.

 

I only added an external filter because of how dark the fluid was. If your fluid is still lightly colored and red, it probably isn't too old. A change most likely won't hurt it. Just drop the pan, drain the converter and change the filter. You should be good to go.

 

If you remove the pan and clean the sediment out, you won't have the trans failure that people talk about. The current fluid has a certain amount of suspended particulate matter because the "filter" is not really much of a filter. When you only flush the trans, without cleaning the gunk out of the pan, then you put fresh fluid in it will pick up all that settled in the pan and then ruins the trans.
I recommend draining and removing the pan, clean it out, change filter, then pull off the return line at the trans, so that you can flush out the trans cooler as well as the tq converter.
I run an external filter on my mud truck, but I've kinda been concerned with the extra restriction. But I haven't removed it. Been there 8 years and its fine.

 

Seems to me that the consensus is that as long as you don't put the thing on a flush machine, you should be fine.

I'm going to go ahead with the drain, filter change, cooler addition and fill routine. Any foreseeable problems running the Valvoline Max Life fluid I intend to use?

 

Drain the Torque converter drop the pan pull the trans filter .Replace trans filter with new one I prefer Motorcraft and pan gasket if needed most of these trans you could reuse trans pan gasket.Install trans fluid .I change My transmission fluid every 30,000 miles .Had a 96 Bronco with 200,000 miles on original E4od was still working fine when I sold it.