Nissan Frontier has different transmission options according to its generation and compatibility with engine types. You can observe the health of their parts based on various symptoms. Visual inspection to see any cracks or damage and a test drive of the vehicle to spot any vibration, whining, or grinding noises are two common methods to assess these indications and their condition.
Symptoms of a Faulty Transmission on Nissan Frontier include slow acceleration, harsh shifting, loss of power, gear slipping, abrupt shifting, and sticking to a single gear. Change in oil condition or diagnostic trouble codes on a scan tool also shows some problems in transmission.
Besides some visual indications, it can also produce fault codes that you can read using the OBD-II tool and interpret them to find the faulty parts. It is better to visit the Nissan authorized dealers or workshop to diagnose the problem and for remedial measures.
Noisy operation of transmission
A faulty transmission will have noisy operation during gear changes or while the vehicle is in motion. You will observe unusual sounds, such as grinding, whining, or clunking. There can be various reasons behind these noises.
Over time, gears, bearings, and other internal parts in the transmission can wear down, generating these sounds. Other reasons can be inadequate fluid levels or old, degraded fluid, which can cause components to rub against each other.
In 2005-2010 models, contaminated transmission fluid with engine coolant can also increase friction and corrosion in moving parts, resulting in vibration and whining noises.
In the 2nd generation Nissan Frontier with 5-speed automatic transmission and V6 engines, you will see symptoms like the vehicle feels sluggish and takes longer to reach speed from the starting point.
Despite pressing the accelerator, the engine will rev high with abnormal sound, but the truck cannot get the desired speed. Worn-out or damaged clutches or bands cannot engage properly, leading to slow acceleration.
Moreover, low or contaminated automatic transmission fluid can cause delayed or inefficient gear changes, impacting acceleration. A faulty valve body or TCM can also cause slow acceleration.
Difficulty in gear shifting
It can cause difficulty in gear shifting, jerkiness, or harsh response, especially at low speeds. Other symptoms can be a grind or clunk sound when shifting gears. It can be the result of broken components or damaged shift solenoids.
Problems with the linkage between the gear shifter can cause difficulty in selecting gears. A faulty brake switch can also cause a harsh response at slow speeds or downshifts.
Contaminated or degraded transmission fluid, worn-out clutch, or bands can also pose the problem of difficulty in gear shifting because of friction. It is easy to prevent this problem by maintaining your truck.
Loss of power
If your Nissan Frontier model loses power after starting or during uphill climbing, it can be a transmission fault. Problems such as a failing torque converter, broken gears, or a slipping transmission can result in power loss.
Few owners have reported loss of power due to no fluid or a clogged filter, leading to a decrease in hydraulic pressure. Automatic transmissions have an oil pump to supply fluid to the torque converter and other components for lubrication and cooling.
A broken spline at the end of the input shaft can also result in the stoppage of the fluid pump, leading to no line pressure and loss of power. Sometimes, rear planetary gears also get stripped on the output shaft, causing no output power despite the throttle.
If internal components of a transmission are worn or damaged, they will not maintain a proper grip, causing it to slip in and out of gears. That symptom is common in Nissan Frontier models in the 2nd generation with automatic gears.
Moreover, other reasons can be contaminated fluid or debris that prevent proper engagement of gears, leading to slippage.
In my 2007 model with a 5-speed automatic transmission, I have found the reason behind slippage is broken shift solenoids, valve body, and a malfunctioning TCM.
Stuck in a gear
Sometimes, the transmission of the Nissan Frontier gets stuck to a particular gear, and no upshift or downshift occurs. It indicates faulty internal parts related to gear shifts, including shift solenoids, a valve body, and a transmission control module.
Wear and tear, and aging of gears, clutch, and transmission bands can also be the reason behind the problem. Low fluid levels can also cause this problem. Shifter linkage or faulty shifter lock switch can also be the other reasons for automatic gears.
For manual transmissions in 1997-2004 models, problems can be with the damaged clutch cable and misalignment of gears.
Electrical or mechanical issues can cause abrupt or harsh gear changes. Without a speed change, the gear will abruptly change from 2nd to 5th or 9th to 5th in the 9-speed automatic transmission for the 2020-2023 models.
It can be a result of bad programming of the control module. Technical Service Bulletin (TSB) from Nissan guides to reprogram the computer to resolve the abrupt shifting of gears issue.
Another reason for the problem is low fluid levels or pressure in hydraulic lines due to a malfunctioning pump. Contaminated fluid or a choked filter can also cause this problem.
Diagnostic Trouble Codes (DTC)
A computer module can generate DTCs due to various internal transmission problems, providing insight into specific issues through the codes displayed on a diagnostic scan tool.
For example, P0744 is a code for a faulty torque converter solenoid valve. P0730 concerns malfunctioning transmission parts like shift solenoids, a valve body, and contaminated fluid.
In 2005-2010 models, Nissan Frontier with contaminated transmission fluid will give error code P1774. DTCs P1731 and P1775 are also related to faulty parts. In this way, you can find if it is malfunctioning by running the scanner tool.
Changes in transmission fluid
Many of its problems arise from low fluid levels or pressure due to blockage or a faulty pump.
Its color is usually red, but with aging and use, it changes to black because of metallic particles and debris. Its contamination due to engine coolant also caused it to become a strawberry-colored slurry.
Increasing temperature indicates a faulty cooler or low oil levels. Therefore, before every journey, use a dipstick to measure its level and observe its color and viscosity to ensure its condition.
You can also sample it after regular intervals and send it to the laboratory for analysis to assess its composition and plan its drain/refill and filter change accordingly.