"James Bond" Oil Slick & Smoke Screen

[CraigK]

I haven't driven my '87 BII AT 4WD on the interstate (I-95) in very hot weather 95°F+ for several years, but did this past weekend while hauling a small trailer. A problem that I'd had previously began to occur again, in fact, occurred several times during this trip.

Near as I can figure, the transmission fluid reaches its flash point and suddenly boils. A huge spray of ATF fluid blows out somewhere under the vehicle, burning on the exhaust system and making a huge blue cloud of smoke and oil spray. Very cool. Unless you are me, or the driver behind me.

I have a small tranny cooler mounted in front of the rad, and have had the tranny looked at for circulation etc., and it all checks out. The engine temp gauge rose steadily during the trip (~90 miles round trip) and I was unable to use my AC, as this caused an additional spike in engine coolant temperature. I used about 2-3quarts of ATF during the trip, most of which is on the underside and hatch of my BII, all over my trailer, and I suspect all over the windshields of several pissed off drivers!

Possible Solutions?
I'd rather not install yet another tranny fluid cooler, besides, I already have one. Several years ago I bought some sort of ATF additive that raised the flash point. This seemed to help a great deal, however, this stuff has either worn out or is gone from the system, and I can't find an additive that is advertised to do this.

I'm thinking that maybe by using synthetic ATF, I can raise the flash point of the fluid enough to prevent further blowouts. It looks like the flash point of synthetic ATF is 80F° or more higher than regular ATF. Has anyone had this kind of blowout experience? If so, what did you do to solve the problem? Can you MIX old regular ATF with new synthetic ATF? Which synthetic grade/type would I use?

As usual, any ideas, help or insight will be appreciated.

CraigK

 

[ForOffRoadDriving]

thats a neat trick, if only you could control it and make it do it on command. unfortunately the only solution i have to offer is a MT swap.

 

[Frank The Tank]

Don't mix synthetic and dino, i've heard it doesn't mix right they always seperated.

it sounds like you have a serious issue going on here, you need to find the root of the problem (not just raise the flash point) i mean, whys it getting hot even though you have a cooler..........

Frank

 

[exbass94]

Don't mix synthetic and dino, i've heard it doesn't mix right they always seperated.

Frank

Whoever told you this doesn't know what they're talking about. All synthetics, whether we're talking about motor oil, ATF, or gear oil are fully compatible and mixable with their conventional counterparts.

To get ALL of the old fluid out, you need to do a flush. If you want to do this yourself and avoid paying a shop $100+ to do it, you need to disconnect one of the cooler lines and put into a bucket or catch pan. Turn the truck on, and the transmission will pump the fluid out the line. After pumping out a quart or two, shut the truck off and top it off so it's not starving for fluid. (Or have someone else continuously adding fluid while the truck is pumping it out) Repeat until all the old fluid is replaced with fresh fluid.

I hear that the vent tube on these trannies frequently get plugged up. This forces the fluid out of the front seal because of pressure build-up or something like that.

 

[AllanD]

Hot weather?

Check your vent line.

It runs off the top of the trans and loops up to the top bellhousing bolts and back.

Mud dauber wasps like to daub mud in the line and then
lay eggs in the end of the line capped with more mud...

Then when the trans gets hot the trans blows oil past the torque
converter (input) seal right onto the hot exhaust pipe.

Consider yourself lucky, often the truck bursts into glorious
flames when that happens.

Though Aerostars are more prone to going down in flames.

AD

 

[Frank The Tank]

I've been reading up..... on mixing.

A lot of people have been using the drain fill method to go to full synthetic (because you can't fully drain the trans from drain plug....)

Other than a few people having issues with excessive slippage out of the synthetic (and fixing the problem going back to dino)........... it appears to be a superior product. if compatible coding is on the label.

The main reason you wouldn't want to mix them simply because the service life of all the fluid will be that of the lesser fluid. whichever breaks down faster..... and that would be the dino.

Frank