Experiencing intermittent transmission issues

So the transmission issues started when going uphill over 40mph, causing the car to go into "safemode" which locks it into 4th. Restarting the car puts it back into first. Then the transmission became slow to shift from 1-2 and 2-3 automatically, but I can slide it over to manual and forceshift just fine. SES light on. Took it in for diagnostics and was told the problem is internal (as in, they don't know) , and it needs a new $6k tranny. Decided to drive her til she's done. Found Bar's Leak AT repair, put it in and the problems stopped, light went off on its own. Fluid w
Experienced mechanics share their insights in answering this question :
Hello.

If your vehicle is losing transmission fluid and there is no noticeable leaks then it may be possible that the transmission is burning the fluid.

I would check the fluid for any signs that the transmission may be burning the fluid, any hints of a burning smell or excessively dark fluid.

If that is the case, and you wish to continue driving the vehicle, you will have to continue adding fluid as you drive. If this is indeed the case, also keep in mind that the issue will likely worsen until the transmission eventually fails.

If you decide to get it fixed, consider YourMechanic, as one of our mobile technicians can come to your home or office to pinpoint the transmission leak firsthand and help you fix it accordingly.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

When and how your transmission shifts is dependent on the position of the throttle in the intake on your engine. Even something as simple as a serpentine belt ties together several engine components; a problem with one of those components or the belt could cause other, intermittent faults.
The issues for this generation of the Maxima were linked to transmission slips and jerks after roughly 100,000 miles. The repair costs went from $2,500 to $3,500, and many owners didn`t even bother fixing the problems.
When the transmission fluid isn`t clean or is blocked by a clogged filter, the internal components won`t have the lubrication they require to function properly. This could lead to shifting issues, grinding gears, slipping transmission or other common symptoms of transmission problems.
Low transmission fluid is one of the most common reasons for a slipping transmission. The most likely culprit is a problem in your system that`s causing the transmission fluid to leak.
The Vehicle Speed Sensor measures vehicle speed. When it fails the transmission can stop shifting or shift late and harsh. A bad VSS may also inhibit overdrive and the converter clutch.
2022-2023 Nissan CVT Class Action Settlement

Nissan agreed to pay over $277 million as part of the settlement to resolve certain defective transmissions claims. The following Nissan models are included in the 2022 Nissan CVT settlement: 2014 – 2018 Nissan Rogue.

Though changing transmission fluid can`t fix mechanical problems, it does make for smoother shifts and can extend the life of your transmission. And even when manufacturers recommend fluid change intervals of 150,000 miles under normal conditions, it may be a good idea to change it more frequently.
Grinding noises, transmission leaks, burning smells, noisy idling, and shifting delays are all common symptoms of a clogged filter.
Transmission failure can be caused by slipping, symptomatic noises, lack of fluid due to leaks, overheating, or outside factors that affect the transmission.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

2013 Ford Focus Transmission Issue. Is it worth keeping the car?
ANSWER : Hi There,
This is a known issue in this generation Ford Focus and some Fiestas with the "Power Shift" transmission and there have been numerous recalls and lawsuits. Although, it is would be difficult to determine how much longer your transmission will last given the fact that you have many new parts, I would not recommend junking the car as it may still provide some valuable life left for you. I would recommend taking it to the dealer to see if these parts may be covered under the recall.

Car jerks when accelerating in reverse & makes grinding noise. Is this a transmission or computer issue?
ANSWER : Hi there. Typically when you hear a grinding noise when you move forward or in reverse it’s usually an indication of a gear fault either in the transmission or another driveline component. If this occurs only when in reverse, it’s likely a damaged reverse gear. It is also possible that it’s a hydraulic fluid issue not supplying enough lubrication or pressure inside the lines to fully open the gear. I would recommend having a professional mechanic come to your location and complete a car is hard to shift inspection, so they can diagnose the source of your issue and recommend repairs that should resolve this problem.

There is automatic transmission fluid in a manual transmission. Is it okay to leave or do I need manual transmission fluid?
ANSWER : This would depend on what the manufacturer recommends. Many manual transmissions do take automatic transmission fluid. If your transmission has ATF in it, it is very likely that it is supposed to have that in there. If not, it is likely that the transmission would not function properly with the wrong fluid. Many manual transmissions will also take engine oil as a lubricant. The best way to know for sure is to check your owner’s manual or call your local General Motors dealership to inquire.

Experiencing intermittent transmission issues
ANSWER : Hello.

If your vehicle is losing transmission fluid and there is no noticeable leaks then it may be possible that the transmission is burning the fluid.

I would check the fluid for any signs that the transmission may be burning the fluid, any hints of a burning smell or excessively dark fluid.

If that is the case, and you wish to continue driving the vehicle, you will have to continue adding fluid as you drive. If this is indeed the case, also keep in mind that the issue will likely worsen until the transmission eventually fails.

If you decide to get it fixed, consider YourMechanic, as one of our mobile technicians can come to your home or office to pinpoint the transmission leak firsthand and help you fix it accordingly.

Can I add Lucas oil "transmission fix" to my transmission fluid to see if it helps my issue.
ANSWER : Adding an additive to the transmission to try and fix a problem will not work in most instances and should only be used as a last resort before getting a transmission overhaul.

Can too much transmission fluid cause speedometer malfunctions?
ANSWER : Hi there. In most cases when you overfill the transmission fluid it can cause excessive foaming of the fluid or possible internal component failure due to excessive pressure inside the hydraulic lines. Sensors like the speed sensors however are rarely impacted by this situation. However, in regards to the possibility of probability of this; I would say perhaps a 10% chance.

Bought a 1999 Chevy Z71 for very cheap. The transmission is out. How should this be fixed?
ANSWER : Hi there. The 4l60e transmission could have two things wrong with it. Either the park arm is not disengaging inside the transmission making the transmission load up but not rotate the drive shaft or the transmission is low on oil. Check the oil on the transmission dip stick and see what the level is. The level must be checked with the engine running. If the oil level is at the full mark, then it is possible that the torque converter may have damaged the pump.

Remove a cooler line and put it into a bucket, and for a brief moment start up the engine and shut it off. If oil sprays out of the cooler line, then the pump is producing pressure. However, if no oil comes out of the cool line, then the pump is not working.

If you need further assistance troubleshooting your transmission, then I recommend having the transmission problem diagnosed by a local expert, such as one from YourMechanic. You will be be able to make a better decision about the car after finding out exactly what’s wrong with it.

Transmission fluid comes up out of the transmission vent tube attached to the transmission dipstick tube
ANSWER : Hi there. Fluid seepage out of the vent tube can sometimes be normal, but can also be caused by overfilling. Has a service been performed recently? Perform a fluid level and condition inspection by having the engine at idle, on a level surface, warmed up engine, and remove the dipstick and cleaning it with a shop towel. Reinsert the dipstick and fully remove to a horizontal position for inspection. Make sure the fluid is not milky, very dark, or has contamination. The level should be in the safe zone marked on the stick.

Have an inspection by a qualified technician determine if any problems truly do exist and provide you with some assurance. YourMechanic has several technicians available that can assist you with a transmission leak inspection and can perform a transmission fluid service if needed.