1999 Transmission trouble

[AJBSC]

I don’t have time nor the tools/shop to work on a transmission myself. Posting for pure internet discussion and speculation before I take it to a shop. See if anyone has experienced exact symptoms.

It’s a 1999 LX470. Transmission fluid was changed maybe 1k miles ago. 297k on it. Vehicle sat at an office for about 2 years driven a couple hundred miles since the fluid change. I’m getting it back in shape again to drive as an extra. Been driving it a couple days a week for business errands and lunch.

What is happening does not seem like a slip to me. Start it up, goes into gear pretty smoothly both forward and reverse. Shifts 1-4 just fine driving. The issue arises when coming to a stop. Drive it like a grandpa stopping very lightly, it goes back into 1st fine at idle, no slipping when taking back off. If I have to stop with a purpose, not a panic stop, but like a light changing or someone giving a late blinker, it won’t shift back into 1st until you get back on the gas. After the first couple of days it did it, I figured out I can just give a real light tap on the gas, maybe 200 rpm worth, and it’ll realize it’s in the wrong gear and downshift back to 1st without slamming into gear.

 

[OEMGUY0720]

So the cruiser ran for approximately 1,000 miles for the last 2 years? Any of those 1,000 miles it towed 8,000 lbs or more possibly in an uphill stretch? The transmission on the 100 series is robust, they are close to bulletproof unless it was subjected to prolonged over-the-limit stress.
From the symptoms you shared I can only see two reasons:
1. AT Fluid could be not enough- you can check this if you loosen the “overflow” plug of the transmission oil pan (not the FILL plug) after 30 minutes of driving around. If there’s zero or not a drop of overflow, fill it up accordingly - refer to the users manual for the proper procedure.
2. If #1 is ruled out meaning all is good has proper level of ATF and still shifts how you described it, you may possibly be looking at a valve body service/replacement just by basing it from how the shifting behaves.
Good luck and keep us posted.

 

[2001LC]

I'd first:

1. I'd check AT wires for damage.
2. I'd do a full 12qt flush with Mobil 1 ATF. Set level to high hot mark at ATF temp of 160F, flat ground, idling, after shifting through all gears.

 

[Maxgrapene]

So the cruiser ran for approximately 1,000 miles for the last 2 years? Any of those 1,000 miles it towed 8,000 lbs or more possibly in an uphill stretch? The transmission on the 100 series is robust, they are close to bulletproof unless it was subjected to prolonged over-the-limit stress.
From the symptoms you shared I can only see two reasons:
1. AT Fluid could be not enough- you can check this if you loosen the “overflow” plug of the transmission oil pan (not the FILL plug) after 30 minutes of driving around. If there’s zero or not a drop of overflow, fill it up accordingly - refer to the users manual for the proper procedure.
2. If #1 is ruled out meaning all is good has proper level of ATF and still shifts how you described it, you may possibly be looking at a valve body service/replacement just by basing it from how the shifting behaves.
Good luck and keep us posted.

Does the '99 LX470 have the A442F transmission? If that is the case there is no overflow plug. I have a 2000 LC and that has the A442F with no overflow plug that I can find. Fill and check level through the dipstick is only option as far as I can surmise.

 

[OEMGUY0720]

My bad, half asleep when I typed this, I was referring to the main AT pan DRAIN PLUG not the fill plug.

 

[excessive]

check your kickdown cable , make sure there is not too much slack

 

[AJBSC]

@OEMGUY0720 Yes, you did read that right. It was my DD for about a year when I first started a business. I was baselining everything. After getting off the ground we bought a new business vehicle, and left the LX at one of our offices for our guys to drive to job sites. Nobody actually drove it so it sat unused for a couple years. That's why it has essentially no miles on it since the trans fluid change. I've now brought it back up to the office that I work out of and I drive it a few days a week to PO Box, lunch, etc. and working out the kinks.