Truck won’t shift out of first gear

I installed a used motor into my pickup and my automatic transmission won’t shift out of first gear. I took a look at the kick down linkage and the vacuum lines, and they seem OK. Do you have any ideas or suggestions, solutions?
Experienced mechanics share their insights in answering this question :
Hello. There are several possibilities here: the vacuum modulator valve, the governor in the transmission, or possibly incorrect fluid level in the transmission. If you would like to have this checked, a qualified professional from YourMechanic can come to your car’s location to inspect the shifting issue and advise on repairs.

How to Identify and Fix Common car Problems ?

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If your vehicle will not shift out of first gear, the problem is not the fuses. The problem could be a shift solenoid, but more than likely, you have an internal transmission issue that will require rebuilding or replacing the unit. The 1-2 shift valve may be the problem.
A transmission may stay in first gear due to low transmission fluid, a faulty shift solenoid, a worn clutch (for manual transmissions), a malfunctioning transmission control module, or broken transmission bands. These issues can prevent proper gear shifting and result in the vehicle being stuck in first gear.
Over time, dirt, debris and other tiny particles can accumulate in the transmission fluid, affecting its fluid properties. This can cause the vehicle to die when you shift into drive or reverse, allow a loss of power, transmission slip, rough shifts or even prevent the vehicle from shifting into gear at all.
The main reason the car won`t go into gear is that the level of transmission fluid in the vehicle is lower than required. If the level is low despite regular maintenance, there may be a leak. Transmission fluid, therefore, is important to ensure that the car`s moving parts are properly lubricated for functioning.
The most common cause of a stuck solenoid is the failure to replace your transmission fluid when you should. Over time, small bits of metal and other debris will get into the fluid (if you`ve ever seen black transmission fluid, this is what causes it). And this is what leads a solenoid to become blocked.
This issue may be caused by a couple of different things. A gasket near the transmission filter where it mounts to the valve body could be leaking causing the hydraulics within the transmission not to engage second gear properly. On the other hand, a shift solenoid may also be at fault.
But a blown fuse No. 38 becomes a likely candidate causing a loss of power to the transmission solenoids.
Your manual transmission gears see a lot of use and over time, they will begin to wear down. The normal wear and tear can cause sticking of the gearshift as the gears fail to engage. This does tend to happen more often with the first two gears because they are the ones that are shifted to and from most often.
Transmission Fluid Low or Poor Condition – Vehicles low on transmission fluid or that are operating with worn out or contaminated fluid are likely to experience hard shift conditions. Lack of adequate lubrication within the transmission can cause several problems, including hard shifting.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My truck won’t allow me to change gears even when pressing the clutch. No gears go in at all. Makes it impossible to drive.
ANSWER : Hello, this concern is possibly the slave or clutch master cylinder failure. These two components use brake fluid to apply pressure for movement of the clutch system. This fluid breaks down in time and causes the seals to fail (leak). A low fluid level would cause this concern as well as internal leakage. Replacement of components would be necessary. This type of concern would need to be inspected. If you’d like, a certified technician from YourMechanic can come to your location to diagnose your vehicle, and possibly replace your clutch master cylinder if need be.

The car doesn’t shift into first gear while it works fine in reverse
ANSWER : The problem could be that the internal transmission pump is weak, or the transmission clutch seals are leaking. It sounds like the transmission will need an overhaul.

I recommend having a transmission mechanic test the pressures and diagnose the problems to verify whether you need an overhaul with a new torque convertor.

Won’t shift out of first unless you let go of gas but it will shift back down and never grab second
ANSWER : If you have all the drive shafts in the front and rear, then you will damage the transfer case or one of the axles if you drive the vehicle and engage the front end. The two different gear ratios will do this. As far as the transmission goes, you have a problem with the governor inside the transmission and may have bad second gear parts. Have a mechanic pressure test the transmission and diagnose the shifting issue for you.

Won’t shift past 2nd gear . It drives normal to 2nd gear but wont shift into 3r – 2000 Ford F150 4×4
ANSWER : Hello – I don’t think this is related to switching back to 2WD per se. There is a shift position sensor on the side of the transmission, and it’s possible that the snow activity caused moisture and/or dirt to get into the sensor. I would recommend a transmission inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

Im having a really hard time shifting into any gear other than 5th in my truck. I have to use alot of force to shift into gear.
ANSWER : You need to have the hydraulic clutch checked to see if it is disengaging the clutch as it should. The clutch is not disengaging and is the cause of the gears not being able to be shifted. You may have a bad clutch or clutch hydraulic system.

My manual car won’t go into gear, it turns on and the clutch goes down perfectly fine. It happened after my gears grinded, the car
ANSWER : If the clutch mechanism is releasing properly, and the shift linkage is not malfunctioning, your transmission will have to be removed from the vehicle and inspected. Once a transmission has been removed from a vehicle, if the problem is a broken or worn part or parts, and the transmission has 100,000 miles or more, the most cost effective approach is to just simply rebuild the whole transmission. There are transmission rebuild kits that are sold just for this purpose. Rebuilding a transmission is no big deal and is indeed easier in many respects than rebuilding an engine. You can rebuild your transmission right in your own garage. You can NOT rebuild an engine in your own garage due to the highly specialized, and extremely costly, machine shop equipment required. Occasionally, mobile mechanics will take on a transmission rebuild job especially as once the mechanic removes the transmission from the vehicle, it is just simply a modular unit that can be easily transported to a mechanic’s shop and rebuilt right there and then returned to your vehicle. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

My 2000 Chevrolet Silverado will not shift into 3d & 4th gear or reverse only into 2nd gear
ANSWER : Hello. Most of the time when this occurs with this noise it is because the sun shell in the transmission broke. This is very common. The transmission would need to be rebuilt to fix it. I would recommend taking it to a transmission specialist for this.

On interstate, gear shift broke and stuck in first gear
ANSWER : There are many designs for the shifter system in vehicles, and unfortunately there is a known weak point in vehicles similar to your year and model of Porsche. Common concerns often lead to a recall where the part is upgraded or the performance market sees the flaw and make a new part to replace the weak component with. There may be more expensive parts. I recommend getting in touch with the dealer about this to see if the manufacturer can take care of this common problem.