Warmng transmission fluid

[zpiloto]

Does anyone know of a way or ideas to warm the transmission fluid for an automatic? When I'm driving and the engine is cold of course the shift points or higher but once the engine is in the normal operating range it still takes up to 5 miles before the the transmission warms up enought to drop the RPMs.

For example It takes about 8 miles to get to the stretch of road where I can get the speed over 45 where the TC locks out. The engine temp has peaked out at about 5 miles or less. Once up to speed at 55 the RPM will be 1850-1900 for about 2 miles and then drop to 1700 where it normaly is at that speed. That 200 rpm has got to be killing me. I am using a radiator heater which work better than nothing but do they make transmission heater or you think a oil dip stick heater in the transmission hole would work? Just brainstorming for inexpensive ideas.

[Gary Palmer]

What are you using for the radiator heater? I would be willing to bet that if you just took the cooling hose from the automatic transmission off of the radiator and fed it back onto the other line, that would help the transmission heat up, significantly. Right now, if your running a normal setup, they run a line to one side of a tube through the radiator and the other side goes back to the transmission. I don't think the radiator coolant is getting warmed up, at all, until the thermostat is at least 20% open, so the poor transmission is acting as an external heater to the radiator.

I would think a dip stick heater would help also.

I would agree on the torgue converter killing your mileage.

[zpiloto]

Originally Posted by Gary Palmer

What are you using for the radiator heater? I would be willing to bet that if you just took the cooling hose from the automatic transmission off of the radiator and fed it back onto the other line, that would help the transmission heat up, significantly. Right now, if your running a normal setup, they run a line to one side of a tube through the radiator and the other side goes back to the transmission. I don't think the radiator coolant is getting warmed up, at all, until the thermostat is at least 20% open, so the poor transmission is acting as an external heater to the radiator.

I would think a dip stick heater would help also.

I would agree on the torgue converter killing your mileage.

I'm not following you. That is how it set up but are you saying to by-pass the radiator all together with the transmission lines? If so how risky would that be as far as overheating without a temperature gauge?

[skewbe]

You wouldn't want to bypass the transmission oil cooler when it was up to temp certainly.

I am concerned that using plug in heaters is a bit like "borrowing from peter".

Which car is this for? Does it have a trans temp sensor or something that could be tweaked?

[MetroMPG]

Originally Posted by Gary Palmer

I would think a dip stick heater would help also.

Those typically don't have enough wattage to help much.

Are you using an EBH now, z? If so, I'd look at mounting an elemental heater down low on the transaxle (somewhere that the radiant heat will reach the oil).

EDIT: whoops, just read you are using a heater. What about one of those old plug-in BBQ charcoal starter elements...

[rh77]

The OEM EBH on the Integra is robust enough to heat the block and adjacent transaxle (it's hot to the touch). In this weather, longer plug-in times are required to achieve peak temp. The transmission functions as if it has been warmed-up and closed loop is attained within seconds. It's still too cold out for the TC to engage (single-digits to teens and 20s). The car is also garaged when it's plugged-in, so the under-hood temps get to be around 70F as noted by the IAT/SG before startup. I'm also convinced that the AT lines that run into the radiator allow a bit of warm fluid into the trans on startup as well, which probably helps a little.

The biggest stinker is having to park outdoors without an outlet. I should carry a 200-foot extension cord to the office and see what kind of reaction I get

RH77

EDIT: More info on the OEM version: it basically goes into the coolant drain plug on the engine block -- which heats the "heart" of the engine as opposed to just the coolant. If you can get an inexpensive OEM version like this, the transaxle may heat up as well. I have the toughest time on cold-starts without the EBH to shift below 3k RPM in the first 5 miles as well. The darn AT has a mind of it's own...

[zpiloto]

Originally Posted by skewbe

Which car is this for? Does it have a trans temp sensor or something that could be tweaked?

I don't want to fool sensors this transmission has 130k with unknown history so I don't want to put to much pressure on it. I'm lucky it's still going.

[Quote]:theclencher
Best bet is to park in a garage.

I've seen people without garages around here in the frozen north build little "doghouses" for their cars and trucks- wish I had a pic- basically a 3-sided and covered plywood box they nose the car into when they park; it covers the car up to the base of the windshield. Don't know it that would do anything for trans temp but it couldn't hurt. [quote]

Actually it's in a garage but the temps can get down to 40-45 when it cold out. The problem, until summer, is the engine rpm never gets above 1500 until above 45mph this mean a really slow warmup.

Does the fluid need to circulate for the transmission to work properly? It would be easy to put a shutoff in the line like a theromostat and then open it after a while to start cooling and circulating the fluid.

[ELF]

Pretty tough to try a heat your tranny oil. There is only 2-4 quarts in the pan depending on your vehicle. For instance my truck has only about 3.5 quarts when you drop the pan to change oil, but has 13 quart capacity. so much of the oil is in the torque converter and would be hard to heat.
I am surprised your rpm won't drop at 40 degrees, my car works fine till the temps are well below freezing.

[MetroMPG]

Why don't you just spoof it? Put a potentiometer on your ECT sensor?

[Gary Palmer]

ZPiloto: Yes, what I was suggesting was to totally 100% bypass all of the cooling to through the external cooler in the radiator. If your in those cold a temperatures, your not going to do anything to hurt the transmission. I had a Mercury Capri which didn't have any cooling to the transmission, at all. They just plugged off both the input and output to the cooler, winter, summer, whatever. The only time you really need the transmission cooler is in the summer, when your driving in very heated conditions and/or under a lot of load. The rest of the time, it isn't really doing much, one way or the other.

I'd just reattach the hoses in the spring time, maybe April, or so.