Check your transmission fluid

[Racket]

Yes, through the dipstick hole!

Obviously would be needed taken into consideration in design.

I'd rather a rigid tube with brackets - I get the concern about vibration introducing noise but maybe some type of mounting insulation would mitigate that and keeping transmission movement in mind for how things are routed. I admit I don't know if there is a big difference between RWD vs. 4WD models.

Keeping it short enough to not be ungainly and flared at the top opening for a small funnel is going to take some thought on dipstick design.

This starts to sound like complicated R&D but really once those hurdles are cleared the ability to extend the product across many models should give an accessory manufacturer a bigger market like the Mustang crowd.

Sponsored

 

[VegasRanger]

So I think mine may be overfilled actually. I took the dip stick out when the truck was cold, hadn’t started it yet because I was just curious. On COLD without the truck on, the oil was all the way to the top of the dipstick. Cleaned it off, did it three more times and same thing. Wth?

 

[Dr3wDrop]

So I think mine may be overfilled actually. I took the dip stick out when the truck was cold, hadn’t started it yet because I was just curious. On COLD without the truck on, the oil was all the way to the top of the dipstick. Cleaned it off, did it three more times and same thing. Wth?

I would look at other threads. I think the fluid is higher before you run it through the gears. Then it drops down.

 

[Big Blue]

So I think mine may be overfilled actually. I took the dip stick out when the truck was cold, hadn’t started it yet because I was just curious. On COLD without the truck on, the oil was all the way to the top of the dipstick. Cleaned it off, did it three more times and same thing. Wth?

Checking it cold and not running will in no way give you any kind of reading of your level. First of all when not running a lot of the fluid will have drained down into the pan. Second the fluid must be hot as it expanse as ot heats up. The only accurate way is with it hot and running after cycling thru the drive mods. People have checked it running cold and say it is one mark lower.

 

[VegasRanger]

Checking it cold and not running will in no way give you any kind of reading of your level. First of all when not running a lot of the fluid will have drained down into the pan. Second the fluid must be hot as it expanse as ot heats up. The only accurate way is with it hot and running after cycling thru the drive mods. People have checked it running cold and say it is one mark lower.

That’s my point exactly. If cold and all the fluid goes to the bottom, shouldn’t the dipstick be barely reading oil at all? Mine was to the very top of the stick. Seems overfilled no?

 

[quangdog]

That’s my point exactly. If cold and all the fluid goes to the bottom, shouldn’t the dipstick be barely reading oil at all? Mine was to the very top of the stick. Seems overfilled no?

No, not overfilled. See, when the engine is running, there is a pump *inside* the transmission which pumps fluid *out* of the pan and up into the internals of the trans. This *lowers* the level of the fluid in the pan. When the engine is shut off, all that fluid drops back down into the pan, raising the level in the pan.

The dipstick reads the level of the fluid *in the pan*. When the engine is first started, and the fluid is cold, once the pump has filled up the internals, the reading will be a little lower than when the fluid is hot, as the fluid expands when it heats, which makes it use up more volume.

TL;DR: If you check it with the engine off, the fluid will always read very high.
If you check it with engine running, but cold fluid, it will read a little low.
*Correct* reading can only be obtained with engine running, and fluid hot.

 

[Loweredon33s]

That’s my point exactly. If cold and all the fluid goes to the bottom, shouldn’t the dipstick be barely reading oil at all? Mine was to the very top of the stick. Seems overfilled no?

It’s pumping when running so the level is lower. Not running means not pumping (unless in auto start stop mode) the fluid goes down when you start it. Almost every automatic transmission is like that.

 

[VegasRanger]

It’s pumping when running so the level is lower. Not running means not pumping (unless in auto start stop mode) the fluid goes down when you start it. Almost every automatic transmission is like that.

Thank you. Makes sense. I’ll check it again tomorrow

 

[VegasRanger]

No, not overfilled. See, when the engine is running, there is a pump *inside* the transmission which pumps fluid *out* of the pan and up into the internals of the trans. This *lowers* the level of the fluid in the pan. When the engine is shut off, all that fluid drops back down into the pan, raising the level in the pan.

The dipstick reads the level of the fluid *in the pan*. When the engine is first started, and the fluid is cold, once the pump has filled up the internals, the reading will be a little lower than when the fluid is hot, as the fluid expands when it heats, which makes it use up more volume.

TL;DR: If you check it with the engine off, the fluid will always read very high.
If you check it with engine running, but cold fluid, it will read a little low.
*Correct* reading can only be obtained with engine running, and fluid hot.

Thank you!

 

[Ranger_Rocks]

Do we know if our oil pump is always running, even in park ?

My old Jeep Grand Cherokee ZJ pump did not run while in PARK. Procedure was to run until hot, momentarily shift through all gears, then check level while in NEUTRAL. Checking while in PARK without the pump running resulted in a false high level.

 

[Big Blue]

That’s my point exactly. If cold and all the fluid goes to the bottom, shouldn’t the dipstick be barely reading oil at all? Mine was to the very top of the stick. Seems overfilled no?

NO! The fluid will drain down out of the transmission and the level in the pan will be higher without the engine running. Once the engine starts the pump will suck fluid out of the pan and spread it out throughout the transmission.

 

[yamahaSHO]

That’s my point exactly. If cold and all the fluid goes to the bottom, shouldn’t the dipstick be barely reading oil at all? Mine was to the very top of the stick. Seems overfilled no?

 

[Langwilliams]

I was thinking if you check it hot an get the correct reading you could check it later cold an get a reference for checking it cold in the future.

 

[JasonTremor]

So I think mine may be overfilled actually. I took the dip stick out when the truck was cold, hadn’t started it yet because I was just curious. On COLD without the truck on, the oil was all the way to the top of the dipstick. Cleaned it off, did it three more times and same thing. Wth?

That is where the transmission fluid will be when checked cold and the engine not running. Fluid level has to be checked while the engine is running and the transmission fluid circulating and up to temperature.

 

[ctechbob]

I was thinking if you check it hot an get the correct reading you could check it later cold an get a reference for checking it cold in the future.

In a perfect world, yes...but.

Torque converters sometimes drain back into the pan when you leave them sit. Longer the time off, the more they'll drain back. That and some might do it more than others. You could probably do it if you took enough readings over a long enough time and figure out out, but that's why they tell you to do it running. The engineers know how much fluid should be in the circuits when it is running and with that information you can get a consistent level.

All they're doing is trying to minimize variables so that they can have one procedure that covers all vehicles using the transmission and all of them can get an accurate reading for the life of the car.

Sponsored