[Bonesteel]

All,

I had posted about our transmission failing on the Ohio Turnpike this past Monday. This was an assumption on my part given the large loss of fluid and the erratic behavior as it happened.

I have just gotten off the phone with the mechanic who has cleaned the engine compartment, refilled the transmission with Honda fluid, and driven the van. He said it had lost three quarts or so of fluid. There is now no leak and the van drives/shifts fine. He drove it for a half hour and took the van on the highway.

Prior to this happening this past Monday I had no evidence of any issue and the only work done on the tranny was normal maintenance doen on schedule.

Has anyone experienced this? What could it have been and since nothing really has changed, won't it just happen again? My fear of course is to get there, start the drive back to NJ and it happen all over again.

Thanks in advance.

 

[New Dad New Van]

By coolant you mean ATF correct?

ATF in the engine compartment could have been the result of a loose ATF dipstick and/or overfilled ATF increasing pressure and forcing ATF out the vent.

 

[Bonesteel]

By coolant you mean ATF correct?

ATF in the engine compartment could have been the result of a loose ATF dipstick and/or overfilled ATF increasing pressure and forcing ATF out the vent.

Yes, ATF.

I'm pretty confused as to how a loose dipstick could have resulted in that much fluid being vented. Also, the ATF was not added to or modified since it was last serviced over a year ago. I have had numerous trips just as long in just as hot weather, so it is really perplexing.

The mechanic is going to drive it again today and see if he can recreate the issue. If not, I'll just have to assume it was some sort of fluke I suppose.

Thanks for the reply,

Jon

 

[0dyfamily]

Jon, it doesn't take much to overfill the ATF in your tranny's sump, thus causing it to entrain air when the fluid comes into contact with moving parts vertically above the sump (where it is not supposed to).

This causes "foaming" of the ATF. Even though ATF has an anti-foaming agent in its additives pack, overfilling can defeat it. Air-entrained ATF (foam) does not exchange heat, lubricate, or transmit shear forces (read this as power transmission) as well as straight liquid, so it gets hotter more quickly.

This can cause ATF to get pushed out of the dipstick hole and vent tube, leaving a mess in your engine bay. I've seen this happen on a Ford Explorer and a Chevy Suburban. If it ends up on the exhaust pipe, it's a smoky mess as well. The Ford in question had its ATF striking the exhaust pipe catch on fire, but only briefly.

Why it happened a year after the ATF servicing? Don't know, but you're not the first case of "delayed foaming from overfilling" that I've heard of.

OF

 

[Bonesteel]

Thanks much OF,

It appears I was wrong in my initial assessment of the last service. I pulled my records and found the last transmission service was December of 2008. It had not been touched since then, other than levels checked by me. I can only assume that the age of the fluid and the heat of the day caused foaming which resulted in the event.

Tony at Maroun's Motors (HIGHLY recommended BTW) has filled the tranny with Honda fluid and all seems fine. I am flying to Akron tomorrow to pick it up and one of his guys is driving my van to meet me at the airport (an hour's drive) for only $40. We're then going to drive back east towards his shop, so if it is going to repeat, it would do it then.

I am now considering my confidence in general on our van for the rest of the Summer driving season. It only has 82k on the clock, and I have not had any other issues. My gut tells me it's time to sell and cut my losses. My primary concern being that this loss of ATF event has accelerated the eventual failure of the tranny. I'll hopefully get a feel for it tomorrow.

Thanks all for your replies and advice,

Jon