EcoModder.com

EcoModder.com (https://ecomodder.com/forum/)
-   EcoModding Central (https://ecomodder.com/forum/ecomodding-central.html)
-   -   EOC in 2000 Dodge Caravan 3 Litre, Auto Transmission; Damaging? (https://ecomodder.com/forum/showthread.php/eoc-2000-dodge-caravan-3-litre-auto-transmission-27368.html)

101Volts 10-26-2013 06:48 PM

EOC in 2000 Dodge Caravan 3 Litre, Auto Transmission; Damaging?
 
I recently started EOCing in Moony a bit, And I was wondering if this would damage the transmission quickly or not; I did read the manual and it says the van can be flat-towed in Neutral at 25 MPH or less for about 15 miles, And the EOCing I was doing would go as high as maybe 57 and then I'd stay in Drive Then when time came to restart the van I'd switch to Neutral and restart it and it would make an odd, Kinda rough or scratchy sound (Imagine a sound similar to a plastic car bumper scratching pavement on a bump) but it was then on and I'd switch to drive to accelerate again. I do like the idea of EOCing but I also would like to not damage the (Automatic) transmission.

On another subject, EOCing has sometimes messed with the Scangauge in this van, Giving it very strange readings like "2.7 MPG Tank" and "RPM: Chinese Symbol" Or whatever popped up. Thoughts?

UltArc 10-26-2013 07:36 PM

Ugh...

Are you in neutral when you are EOCing?

It doesn't seem like a very good idea if it's for any longer. Neutral doesn't have anything going on with it, put I would not advise it being in drive.

I would put it in Neutral, hit the kill switch, then ride it out until you are ready, then start the engine, and back to drive.

101Volts 10-26-2013 10:34 PM

Quote:

Originally Posted by UltArc (Post 397085)
Ugh...

Are you in neutral when you are EOCing?

It doesn't seem like a very good idea if it's for any longer. Neutral doesn't have anything going on with it, put I would not advise it being in drive.

I would put it in Neutral, hit the kill switch, then ride it out until you are ready, then start the engine, and back to drive.

I'm not sure what you meant about the part I underlined.

And no, I wasn't in neutral for most of the coast; I only set it to N for the restart as it won't start in drive.

The sound happened when I restarted it on the occasions I did this EOCing, Not while I had it in drive while gliding.

And I don't have a kill switch for it at the moment.

UltArc 10-27-2013 12:28 AM

If it's for longer than what's recommended by the manual, sorry, sometimes I don't write out all of my thinking.

I'd go neutral, I imagine drive isn't very good for it- but I don't know your vehicle, just general autos. I try to be careful w/ autos and EOC, I'd utilize a kill switch if you plan on doing it fairly often. If it's for shorter period of times, I would think it would be okay as long as the transmission has time to cool off. I imagine it would need it, if it has those descriptions in the manual.

I'm not an expert, but I'd try to follow the guide as well as possible- at least the principles it suggests.

jaylhouse 10-27-2013 09:59 AM

Just a thought. Is it possible by keying off while in drive, the torque converter was still locked? When shifting to neutral, the engine has nit completely spun down, causing the noise. I had an f150 years ago Restart at 15 mph shifting from neutral to drive. just an idea

101Volts 10-27-2013 03:34 PM

Quote:

Originally Posted by UltArc (Post 397099)
If it's for longer than what's recommended by the manual, sorry, sometimes I don't write out all of my thinking.

I'd go neutral, I imagine drive isn't very good for it- but I don't know your vehicle, just general autos. I try to be careful w/ autos and EOC, I'd utilize a kill switch if you plan on doing it fairly often. If it's for shorter period of times, I would think it would be okay as long as the transmission has time to cool off. I imagine it would need it, if it has those descriptions in the manual.

I'm not an expert, but I'd try to follow the guide as well as possible- at least the principles it suggests.

Thanks. I'm not sure what to do for an on-off switch though, I tried taking the fuel injector fuse out which turned the injectors off without touching the key but when I put the fuse back the van didn't restart (Edit: It didn't restart the fuel injectors) until after the key was turned off and to "Start" Again, So I don't think attaching an on-off (Normally on) switch to the fuse would work.

Quote:

Originally Posted by jaylhouse (Post 397121)
Just a thought. Is it possible by keying off while in drive, the torque converter was still locked? When shifting to neutral, the engine has nit completely spun down, causing the noise. I had an f150 years ago Restart at 15 mph shifting from neutral to drive. just an idea

I don't know, But that's a good thought about the TC being locked. The last time I restarted from an EOC was at about 45 MPH and I've noticed the odd sound at speeds like about 30. I'm not sure how it would sound above 50.

Quote:

Originally Posted by 101Volts (Post 397082)
... And the EOCing I was doing would go as high as maybe 57 and then stay in Then when time came to restart ...

Fixed - "And then I'd stay in Drive." Sorry!

t vago 10-27-2013 10:49 PM

When Chrysler transmissions (and, I suspect, many others) are driven from the drive wheels while in neutral, there's still some friction going on inside the transmission itself. Normally, this is not really a concern because the engine would be running, therefore would be driving the transmission fluid (oil) pump, therefore would be providing transmission fluid to cool off those moving parts that are being driven.

The whole reason why it's not advised to go in neutral for more than a few miles, while the engine is turned off, is because there's really nothing that will drive the transmission fluid pump, so those moving parts will tend to overheat and eventually fail.

That noise you're hearing is likely something that expanded due to heat buildup from friction, rubbing against something else that is being driven off the engine, and it goes away because there is now transmission fluid flowing over the overheated parts, cooling them off, and in the process causing them to shrink back to normal size.

Recommended Vehicles : Remco <- You might want to look into something like this, that will pump transmission fluid throughout your transmission, even with the engine turned off. Heck, I might even look into it.

UltArc 10-27-2013 11:20 PM

What about if it is in Drive, like the OP is doing it?

t vago 10-27-2013 11:50 PM

Quote:

Originally Posted by UltArc (Post 397201)
What about if it is in Drive, like the OP is doing it?

The answer depends on three things - selected transmission gear, the stall rating of the torque converter, and the vehicle speed. If all three are such that the transmission can still turn the engine over, even if it's turned off, then the engine turning will then drive the transmission oil pump. As long as the transmission oil pump continues to be driven, then it is still circulating fluid throughout the transmission.

I see this happen fairly regularly with the Karen-mobile, in fact. Whenever it enters DFCO (normally in D at speeds above 50 MPH and with no pressure on the gas pedal), the engine computer will cut power to the injectors, and the engine will still turn over, due to the fact that the drive wheels are now driving the engine through the transmission. Below about 50 MPH, though, the engine computer will "start" the engine again by re-energizing and driving the injectors as before. I suspect that if this did not happen, the engine would probably come to a stop at some point not far below 50 MPH, as transmission oil pressure would drop to a point where it could not hold its selected gear any longer, thus disconnecting the drive wheels from the engine.

UltArc 10-27-2013 11:52 PM

101, that seems like the best answer you're going to get!


All times are GMT -4. The time now is 10:02 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com