Another A750F issue

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Dec 18, 2021
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14
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Doha
Just purchased a 2004 GX470 228k miles, never test drove it cold. I drove from LA to Salt Lake City and always let it get to operating temperature. It drove flawless, and never missed a shift, flared, hunted or delayed in shifting. I stopped in Salt Lake City and let a Toyota dealer install two new OEM front axles; great price on parts and install. Told the service advisor I was pretty happy with the car, he responds with something about other than the transmission issues. Thinking he's full of it, I get in my vehicle, warm it up and set off. No more than a mile down the road it's not shifting from 4th to 5th/OD. I bring it right back and let him know the issue. He's telling me I brought him a car with unknown service hx etc etc. I advised there was no documentation of a transmission issue by him, but a service request for about 5-7k in other work, because of unknown service hx. Told him lets move forward and trouble shoot it with the tec. The tech hooks up techstream and code P0776 shows. He resets the trans and puts it on a lift, drops the fluid, looks good to the eye. He replaces what he dropped, about 3.5 qts and on test drive it now shifts from 4-5/OD.

The next morning I shift it cold and there's the delay and clunk into D and R. Once this vehicle is at operating temp it seems flawless. Well the issue into R cold is stronger than D. It really wont shift into R until its full operating temp. I'm taking it to a shop tomorrow to do a cold line pressure test. I'm hoping its low on the cold line test, and it's just the valve body that needs repair.

I noticed on the trans it has beens scribed with the marks of a trans shop in Garden Grove, Ca. Contacted that shop and gave him the date hoping he would provide what service he provided. No luck in him getting back to me.

I was in a time crunch to buy the vehicle. Really thought I covered my bases with my mechanical knowledge and hx. Lesson learned, shift it cold.
 
Just purchased a 2004 GX470 228k miles, never test drove it cold. I drove from LA to Salt Lake City and always let it get to operating temperature. It drove flawless, and never missed a shift, flared, hunted or delayed in shifting. I stopped in Salt Lake City and let a Toyota dealer install two new OEM front axles; great price on parts and install. Told the service advisor I was pretty happy with the car, he responds with something about other than the transmission issues. Thinking he's full of it, I get in my vehicle, warm it up and set off. No more than a mile down the road it's not shifting from 4th to 5th/OD. I bring it right back and let him know the issue. He's telling me I brought him a car with unknown service hx etc etc. I advised there was no documentation of a transmission issue by him, but a service request for about 5-7k in other work, because of unknown service hx. Told him lets move forward and trouble shoot it with the tec. The tech hooks up techstream and code P0776 shows. He resets the trans and puts it on a lift, drops the fluid, looks good to the eye. He replaces what he dropped, about 3.5 qts and on test drive it now shifts from 4-5/OD.

The next morning I shift it cold and there's the delay and clunk into D and R. Once this vehicle is at operating temp it seems flawless. Well the issue into R cold is stronger than D. It really wont shift into R until its full operating temp. I'm taking it to a shop tomorrow to do a cold line pressure test. I'm hoping its low on the cold line test, and it's just the valve body that needs repair.

I noticed on the trans it has beens scribed with the marks of a trans shop in Garden Grove, Ca. Contacted that shop and gave him the date hoping he would provide what service he provided. No luck in him getting back to me.

I was in a time crunch to buy the vehicle. Really thought I covered my bases with my mechanical knowledge and hx. Lesson learned, shift it cold.
The FSM procedures for this code on a 2005 (PDF pages P0776) mention possible causes being the SL2 shift solenoid, the valve body itself, and the whole transmission. If you do replace any valve body parts, I'd strongly suggest also having the transmission internal wiring harness replaced, which is only a ~$60 part from the dealer. A few others on here and myself have had transmission codes and other issues caused by increasing resistance in the harness as it ages (there is also one report of a harness leading to the wicking of transmission fluid all the way up to the ECM).
 
The FSM procedures for this code on a 2005 (PDF pages P0776) mention possible causes being the SL2 shift solenoid, the valve body itself, and the whole transmission. If you do replace any valve body parts, I'd strongly suggest also having the transmission internal wiring harness replaced, which is only a ~$60 part from the dealer. A few others on here and myself have had transmission codes and other issues caused by increasing resistance in the harness as it ages (there is also one report of a harness leading to the wicking of transmission fluid all the way up to the ECM).
I will certainly oder that part. Pretty sure this valve body is coming out, and hopefully that's all. Anyone here have IPT rebuild their valve body? I wanted to go with a Nomad, but the 6-7 week time isn't working for an incoming Ottawa winter.
 
I have the Nomad and love it. If you can delay the repair until the Nomad gets here that would be preferable. Mine was shipped via US stock in 2022 back when Cruiser Brothers was still around and sold them.
 
The insanity of this situation is beyond me and highlights the problems with the auto industry. I took it to a transmission shop and they ended up charging me $220 to adjust the overfilled transmission and failed to do a proper diagnosis. I specifically asked for a cold line pressure test, but that advised me they don't do them.

So to warm the trans up to proper temp, remove the check plug it's $220. Tomorrow I'm on my way to harbor freight to purchase a trans pressure gauge, and some impact sockets. I'm better off on doing this myself. Line pressure test, remove the y pipe, and drop the pan.
 
The insanity of this situation is beyond me and highlights the problems with the auto industry. I took it to a transmission shop and they ended up charging me $220 to adjust the overfilled transmission and failed to do a proper diagnosis. I specifically asked for a cold line pressure test, but that advised me they don't do them.

So to warm the trans up to proper temp, remove the check plug it's $220. Tomorrow I'm on my way to harbor freight to purchase a trans pressure gauge, and some impact sockets. I'm better off on doing this myself. Line pressure test, remove the y pipe, and drop the pan.
It's not just the auto industry, it's every industry. I've DIY'd everything on my vehicles for 20+ years and now also DIY everything at home short of pouring concrete. Most "professionals" these days have a great gig of over-charging customers for low-quality work that is done behind schedule. The shortage of talent relative to market demands many they can get away with it again and again.
 
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