₦airaland Forum

Automatic transmissions, are sweet to drive, but when their failures are about to set in, it can be fustrating, and sometimes, a money pit fixing or replacing them.

I will suggest, if one has got transmission issues, to instead, weigh, replacing electrical parts, such as solenoids, if they are the culprits, than the mechanical parts like, clutches, and so on.

Outrighy replacing the transmission because of a shift issue, that could be attributable to those solenoids, in my view would be costly.

So, i have put together, a few transmission jobs i have tackled some weeks ago, hoping that this will be of benefits to you guys.


CASE STUDIES:
1. ES350 2009
The transmissio on this vehicle is higjly sensitive.
You got to be careful the kind of fluids used in the system.

Complaints:
Transmission in drive, is sluggish. Takes time to respond, when accelerating on takeoff.
If it eventually takes off, there is this jerky feeling during gear changes. After that, all gears selects without issues.

Discoveries:
Transmission has burnt smell, and black as a dead engine oil, with soots present.

Diagnosis:
Retrieved a P0776 solenoid B kind of code, and an oxygen sensor.

The fix:
1. Drained the transmission fluid, which was actually dead black. Owner says fluid was replaced January 2023

2. Performed resistance, continuity, and voltage test on the transmission wire harnesses, and solenoids.
Those tests helped us determine if it was only a solenoid or two that needed to be replaced.

During resistance and continuity tests, always be handy with your vehicle's brand specification values.

For instance, resistance test values recomended for Toyota
/Lexus is 5.0-5.6ohms @ 20°C, or in some cases, 5-6.00ohms.

During my tests, all solenoids(SLT, SL1, SL2, SL3, etc), measured 5.6ohms, while the suspect one, SL2, was 7.8ohms, which was out of spec.

That solenoid, was replaced with a known good one.

3. Removed the other solenoids, and serviced them, as did the one replaced.

4. Washed or cleaned off the dirts from the valve body of the transmission, considering it was too dirty.

5. Reinstalled the valve body, after using light silicon grease, to hold off the spring, and checkball in its place to make it easier to install.
Without doing this, the checkball and spring would be a formudable task installing before the valve body.

6. Replaced the transmission filter with a new one

7. Installed the transmission pan, after lightly applying silicon sealant.

8. Introduced Toyota WS transmissiin fluid, to the right level.

9. Reset the memory of the ECU, since amother solenoid was replaced.

10. Finally carries out adaptive driving so that the vehicle relearns what has being done.


PS: always test all solenoids in the transmission. Do not rely on the culprit solenoid. Some solenoids could be fault or hve failed, without even trivgeeing a code to be retrieves by the computer.

Can not llst pictures here. What is going pls?

TRYGO:
Can not llst pictures here. What is going pls?

happen to me too, reduce the size of the picture and try again

Nice one.
How was the test drive after repairs?

My pictures are not uo to 4MB, yet can not upload them here.
I will upload them on my websites, so that anyone interested would view them and apply same to their vehicles.

U660E transmission valve body, with the solenoid wire harnesses being visually checked for fragility.
If one can, I will prefer to replace a failing senoid, than totally having the whole unit replaced

Had to remove the solenoids individually, for cleaning. This helps with organizing them, so that they do not get mixed up. They somehow look similar too.

The SL2 solenoid was the one replaced, in this case.
It is the second, from left, with the brown connector.
You identify this one by the 4 number of slots or ports inline with the solenoid's connector.

Case study two, is a Toyota Matrix 2009, with transmission issues too.

Complaints was that when vehicles comes to a traffic stop, there feels a terrrible shudder from the bonnete area, as though the transmission is about to fall off. It is that feeling of being rear ended (as though somebody hit you from behind). It is such a terrifying experience. At that point, the transmission reengages itself again, and everything smoothens out.

Scanning this vehicle, we retrieved the following codes:

1. P0016. This relates to a misalignment of the timing chains on the crankshaft and camshafts.

2. P0746. This relates to the transmission problem customer complained about.
It is basically a hydraulic line pressure control problem,where the SLT solenoid, acts as the upstream fluid source(this time not functional), that discharges its 'tributaries' downstream to replenish the transmission bands, clutches, brakes and so on.

A blockage, or malfunction on the part of this solenoid valve, would starve other solenoids lime the SL1, SL2, etc from accessing transmission fluids, necessary to pressurise, and make the transmission's engagement smoother.

The Fix:
1. Transmission fluid drained, with the transmission filter removed cause it was clogged.

2. Performed voltage, resistance and continuity tests of the solenoids, and their wire harnesses for signs if shorts or open circuit proems.
During these tests, using a digital voltmeter, it was observed that the suspect solenoid, SL1-A, was within range, but on voltage application, plunger of the solenoid moves slowly instead of faster. Solenoid was not ok. Got to replaced it.
But the suprising thing discovered was, on testing the resistance of the SLT solenoid, it was within spec tol, but performing voltage test, showed it was stuck, and somewhat shorted internally.

Continuity teats between the solenoid +ve and -ve terminals to ground, and wire harness to geound also checked out perfect.

3. Replaced the transmission filter also in this case, like I did for the ES350 transmission.

4. After individually servicing the kther somenoids, and replacing the failing ones, SLT, and SL1, before installation of the valve body, apply a thin light silicon grease to the checkball, and spring, in order to hold them in place. Without doing this, it will be difficult to mount the valve body easily.

5. Lightly applied transmission fluid to the rubber seal on the transmission filter before installing it, and securing it firmly by torquing the 3* 10mm bolts.

6. Applied silicon seal on the transmission pan, and tightened the pan. Allowed it to set for about 5 hours, before a new 4 liter WS transmission fluid was introduced.

7. Reset the memory, and prepared the vehicle for adaptive test drive, where the ECU, relearns the operation of the transmission.
Disconnecting the battery terminals, and reconnecting it back, will not reset the system.



Regards,
Joseph

U250E transmission(13pin), transmission valve body exposed with the pan already removed.

The valve body removed, with the pan

The transmission valve body fully on display

These are some of the switches(non solenoid) on display

Digital meter used to perform resistance, continuity tests.
Always carry this out, to eliminate electrical issues.

Here is a short update guys!

For the matrix, the "emergency surgery", could not save the transmission.
The reason being that the transmission was left to have deteriorated to the point it was.
According to the car owner, she thought when ut started with a sort of shudder, it will disappear on its own.

PS: Make it a point to seek for 'medical' help, when you observe any unususalities with your vehicle's performance.
Early attacks on a tumor, with the right information, can prevent the spread of cancer to other parts of the body.


*Joseph*

TRYGO:
Here is a short update guys!

For the matrix, the "emergency surgery", could not save the transmission.
The reason being that the transmission was left to have deteriorated to the point it was.
According to the car owner, she thought when ut started with a sort of shudder, it will disappear on its own.

PS: Make it a point to seek for 'medical' help, when you observe any unususalities with your vehicle's performance.
Early attacks on a tumor, with the right information, can prevent the spread of cancer to other parts of the body.


*Joseph*

It is always funny when people post "used by a woman" in their car adverts because most women don't take care of their cars at all

yak:
It is always funny when people post "used by a woman" in their car adverts because most women don't take care of cars at all

Is this necessary?

Hello bosses. Good day.

Please I use a Nissan Altima 2008 2.5s.

I recently just changed the car's engine cos the previous one got knocked. Since I changed th engine, I've not enjoyed the car at all. The first issue was the car not revving at all which was partially fixed by the mechanic by replacing the injector mouth( throttle body). After replacement, same issue occured until a rewire checked it out and the car started revving. Also to mention, the car on idle is high around 1300-1500 rpm. It also doesn't start once in the morning until after like 3 to 4 times.

Now the main issue I'm facing is this. Once I engage the gear, the car looses power and accelerates very sluggish and once I put the car back to Neutral or Park, it doesn't rev well and the raising is sluggish. But once I switch off the car and ON again, the car revs well, once i engage gear, it looses power again even when returned to neutral or Park. Please Help

TemmyDayo50:
Hello bosses. Good day.

Please I use a Nissan Altima 2008 2.5s.

I recently just changed the car's engine cos the previous one got knocked. Since I changed th engine, I've not enjoyed the car at all. The first issue was the car not revving at all which was partially fixed by the mechanic by replacing the injector mouth( throttle body). After replacement, same issue occured until a rewire checked it out and the car started revving. Also to mention, the car on idle is high around 1300-1500 rpm. It also doesn't start once in the morning until after like 3 to 4 times.

Now the main issue I'm facing is this. Once I engage the gear, the car looses power and accelerates very sluggish and once I put the car back to Neutral or Park, it doesn't rev well and the raising is sluggish. But once I switch off the car and ON again, the car revs well, once i engage gear, it looses power again even when returned to neutral or Park. Please Help

Scan the car first