Transmission failure P0756

So I'm hoping to get some help from you all. Also Hi I'm new here. I have 2015 5th gen SR5 4x4 73K miles. I was driving down the road to the grocery store. Very short distance. Then my transmission felt like it dropped in neutral revving high then dropping back into gear (did this one time). Then I get to the store and try to leave and I have no reverse. So I pull out straight and the way the roads are set up I'm forced to take the highway home now. At this point I noticed that it won't go past 3rd or 4th gear and dropping in out neutral. Throws one code. P0756. So I granny it home. Code says it's shift solenoid B or wiring. I did some research and this stuff can be caused by low transmission fluid. Should I change the solenoid or just try and add fluid to the transmission. I wanted to some fellow 4runner owners opinions on this.

 

Welcome. First course of action will be checking fluid level and it's condition in any transmission diagnosis. But, don't just try and add fluid without checking the level first, as overfilling can cause damage unrelated to the problem. Hopefully you have a competent mechanic or dealer close by that can recommend a good course of action if the fluid is not the issue.
Has the trans ever been serviced? I had the local dealer do a drain and fill at 100k miles and they reported that the old fluid was black.
Checking the fluid level in the A750 that does not have a dip stick (all 5th gens) is a little involved. The fluid temperature in the pan has to be between 115 - 130 F to be checked properly. Here is the pdf that is from the service manual. Good Luck!

 

Better hope it's shift solenoid B.
Tranny on 4runners can go to 300,000 miles (some without ever having a drain and fill = 5 quarts AW at a dealer - 13 quarts total).

How do I know this? A few owners have posted they never changed theirs at 250,000 miles!

Take it to a dealer and let them check it out. They will do a 5/6 quart D/F.

There's no tranny dip stick on new Toyotas4runners - 2005 and up. Toyota only wants professionals to check and service their transmissions today.

Unless you have transmission fluid leaking on ground, those units are sealed and don't need tranny fluid.

Use only Toyota brand tranny fluid.

SR5 2005 (original owner) 150,000 miles V6 = no engine or tranny problems in 15 years.
No codes tripped in 15 years.

My AISIN transmission shifts perfectly with just one 6 quart D/F by the dealer at 103,000 miles.
I requested the D/F.
Toyota Manual does not show a maintenance schedule for
5 speed automatic.

Let a good T dealer D/F your tranny fluid.
Level is important and they will change your filter
all for about $100 to $120.

$58 Toyota 00289-ATFWS Lexus & Automatic Transmission Fluid WS ATF World Standard, Pack of 4

Amazon.com: Toyota 00289-ATFWS Lexus & Automatic Transmission Fluid WS ATF World Standard, Pack of 4: Automotive

 

Definitely sounds like you’re either low on fluid or the like the code says, solenoid failure. We had it happen on an 01 suburban, blew a solenoid on a 8 hour drive home. Drive it home in second gear for 5 hours at 4200RPMS the whole way.

 

They're not "sealed" and do need a drain and fill every 50k or so. I almost want to assume this is a troll post

 

your fluid is likely black by now

 

Toyota auto fluid tends to go black rather quickly. And generally speaking, changing oil on a high mileage tranny is asking for trouble. Especially on a tranny that's been working hard pulling heavy loads etc. This from the head of technical department of Aamco, who was a tech for 25+ yrs.

My 2007 FJ had 75k miles on her when I flushed the oil myself, really not that hard to do as long as you have someone with you. You know you're at the right quantity of oil when the oil barely trickles out of the fill port at around 115*F as was previously mentioned