Issues To Look Out For In The Jatco 5R05 Transmission
Posted by Regis F. on Monday, September 9th, 2013
The Jatco 5R05 is an automatic transmission made jointly with Nissan. It has five forward speeds and is designed primarily for rear wheel and four wheel drive vehicles. It was first put into production in 2002 and remains in production today. The 5R05 can be found in the Nissan Armada, Navara, 350Z, Pathfinder, Xterra and Titan. It’s wide spread use means that one is bound to end up in your shop sooner or later for service work or repairs. Let’s take a look at some of the possible problems you may encounter with this transmission.
The 5R05 transmission is primarily used in heavy vehicles. Most of them are equipped to tow (with the exception of the 350Z) and that’s where problems can occur. Owners often tow over the factory recommended tow limit. This can be very hard on an automatic transmission. Clutches can slip and the transmission can overheat.
Ideally you want to keep the temperature of this transmission under 200 degrees. For every 20 degrees you go over 200, you risk the possibility of cutting the expected lifespan by a factor of two. As the temperature rises, things can quickly snowball. At temperatures as low as 240 degrees the transmission fluid can start to turn to varnish.
You can do two things to help your transmission battle excessive heat. The first is to install a high quality aftermarket transmission cooler on your vehicle. Second, switch from organic oil based transmission fluid to one that is synthetic. Don’t forget to buy a transmission temperature gauge so you can keep an eye on the transmission temperature. Finally, don’t tow over the factory tow limit!
A weak part in the transmission is the solenoids used for shifting the transmission and controlling the lockup torque converter. The solenoids are nothing more than an electric/mechanical magnet that moves a valve in the valve body. The magnet is made up of a long coil of fine wire that when energized, creates a magnetic field.
The coil of wire in the solenoid can fail in two ways. First, the wire can break. This is usually the result of excessive vibration. Second, the wire can internally short out. This is usually the result of excessive heat causing the protective plastic coating to melt off the wire. Both conditions can be verified using an ohm meter. If the wire is broken you will get no reading. If the wire is internally shorted you will get a low reading. Refer to the shop manual for correct readings.