AT 1-2 cold shift not hard if step thru gear first

[youdontwannaknow]

This is something I have been observing for a while on both cars but more noticeable on the MDX.

On a cold start (after sitting overnight) the very first shift of the day from 1st->2nd gear is hard (almost like a prolonged stretched out shift unlike a fast quick shift) but before starting off if I shift the stick to 2nd gear while the car is stopped with brakes applied and engine running (D->2 and then back from 2->D), then the 1->2 shift becomes very smooth. As if momentarily engaging 2nd gear made something happen because of which it no longer shifts hard in that gear.

All along I was thinking it could probably be due to the viscosity of the atf when its cold but since the smooth shift does happen after the 2nd gear is manually engaged once, that is ruled out.
So what do you think explains this ? Whats going on ?

 

[J. A. Rizzo]

My Pilot does the same thing. Not sure of the explanation, but I know other Pilot and MDX owners who say the same thing. It's never been a problem AFAIK, so I just don't worry about it. It seems more pronounced as the weather gets colder also, so I was also thinking something along the lines of ATF flow at cold temps, but don't have any way to test or prove it out.

 

[Colt45ws]

So Hondas will actually lock in 2nd gear if you call for it on the shifter? I know my Ford will, but the GM cars Ive been in, its just a lock-out of everything above 2nd, so it will still start out in 1st. LAME.
I would guess it probably fills the 2nd gear circuit so that when it calls for it again, the fluid does not have to fill a dry passage and accumulator. Which will take a bit of time since the fluid is cold. Im sure if you went manual 2nd while moving you would get the same 'harsh' shift. You just dont feel it since you are not moving.

 

[charbaby]

Originally Posted By: J. A. Rizzo
My Pilot does the same thing. Not sure of the explanation, but I know other Pilot and MDX owners who say the same thing. It's never been a problem AFAIK, so I just don't worry about it. It seems more pronounced as the weather gets colder also, so I was also thinking something along the lines of ATF flow at cold temps, but don't have any way to test or prove it out.


My wife's 01 Lexus RX-300 AWD does the same thing.
I drove our friends 07 Pilot yesterday and it too did the same.

 

[youdontwannaknow]

Originally Posted By: J. A. Rizzo
It seems more pronounced as the weather gets colder also, so I was also thinking something along the lines of ATF flow at cold temps, but don't have any way to test or prove it out.

yes I forgot to mention that. the colder it gets and longer it sits, more pronounced is this effect.

Originally Posted By: Colt45ws
So Hondas will actually lock in 2nd gear if you call for it on the shifter?

yes. but only 2nd. all others are "up to" that gear.


Now just to make sure - all of you who said the Pilot and RX does the same thing - you mean not just the hard shift, but also the smooth shift after manually stepping into 2nd before you start off, right ?

 

[charbaby]

Originally Posted By: youdontwannaknow
Originally Posted By: J. A. Rizzo
It seems more pronounced as the weather gets colder also, so I was also thinking something along the lines of ATF flow at cold temps, but don't have any way to test or prove it out.

yes I forgot to mention that. the colder it gets and longer it sits, more pronounced is this effect.

Originally Posted By: Colt45ws
So Hondas will actually lock in 2nd gear if you call for it on the shifter?

yes. but only 2nd. all others are "up to" that gear.


Now just to make sure - all of you who said the Pilot and RX does the same thing - you mean not just the hard shift, but also the smooth shift after manually stepping into 2nd before you start off, right ?


Yes, my RX has a button(ESC SNOW) near the shifter that will select 2nd gear. I can either select the 2nd gear to start off with(as in slippery conditions) or press the button at any time while in 1st gear and it will automaticly/right away, shift into 2nd gear smoothly but, will not hold 2nd gear as in a Honda. For that, I would have to pull the shifter down into "2" and it will hold 2nd gear that way. Pulling down the shifter into "2" while starting off will still allow a 1st to 2nd shift and hold 2nd from there. I have had Honda's so, I know how they work as well.

 

[unDummy]

How old is the ATF? what type? and its maintenance history?

 

[charbaby]

Originally Posted By: unDummy
How old is the ATF? what type? and its maintenance history?



UnDummy, I'm not sure who you were asking but, for me, I have changed the ATF w/T-IV since new every 12 months or so. I just did a drain and refill in June'09 Castrol IMV and eveything is the same/fine/same as before! Although I could swear that when the vehicle was brand new it never did this and then, it happened one year/winter and has been like this ever since even after resetting the ECM/disconnecting the battery. Changed the battery two years ago in NOV '08 and still the same. This should have reset the computer too!

In the spring/summer of 2011, I may lay up the RX for a couple of weeks and fix some things. I may replace the high pressure P/S line and any other steel line that I don't like the looks of. I need to clean the IAC valve, and I want to check/clean the TB. Already spray cleaned the MAF with the MAF spray cleaner. Also, I want to do an ATF pan drop change the screen/filter and clean any transmission sensors/solenoids. Maybe even change out the transfer case and differential fluids again, IDK! Have been using Mobil 1 75W90. Usually bleed the brake system every couple of years and check the brake system/components. Belts, hosed etc.


The RX is a nice comfortable SUV/CUV and I just want to stay on top of things.

 

[unDummy]

It was for the thread starter. And, cold weather programming isn't something we can change. Try a full synthetic ATF next time.

OP disappeared??

 

[youdontwannaknow]

I never get thread reply emails. I have given up trying. just one of those quirks of bitog I guess. so I just search for threads that I expect replies to when I log in next.

ATF is Z1. Last change was about 6-7k ago and since ~40k on the car the fluid change has been every ~15k or so.