The 4L80E Transmission is a fully computer controlled transmission that comes bolted to the higher horsepower and torque trucks. It is the overdrive successor to the 3L80(better known as the TH400 for most of it’s life). It is significantly larger than the 4L60E and if you compare the cases side by side it makes the … Read more
This short guide is will hopefully help you diagnose simpler Allison Transmission problems. Allison Transmissions have been around for a hundred years and have set the industry standard for durability. The odds are pretty good that you’ll never find your way here, but if you did lets get this figured out! Limp Mode on … Read more
What are the major differences between the 4L60E and 4L65E transmissions? If there were a one-word answer to this question it would be strength. The 4L65E is manufactured to handle more torque than its counterpart. They have an identical looking case. For all intents and purposes the 4L60E became the 4L65E when GM upgraded some … Read more
The M30 transmission is a variation of the venerable 4L60E transmission, and is manufactured by General Motors. It has four forward gears, the third of which is a 30% overdrive. M30 itself is a RPO code. It stands for: M30: TRANSMISSION, AUTO 4 SPD, HMD, 4L60E, ELECTRONIC There is a different RPO code for every … Read more
The GMPT 4L60E is a GM automatic transmission. Some 4L60E’s will have this stamped on the case, usually on the bellhousing portion. The GMPT itself stands for General Motors Powertrain. It’s similar to the way that MD8 was stamped onto the 700R4. GMPT Folklore. Many enthusiasts see this stamp on the case and get … Read more
Back in the day, when you’d go to start a car it would be entirely possible for you to bump the starter and have the vehicle just take off. This would cause damage to property, other vehicles, and even human life. The Neutral Safety Switch was invented to curtail this issue. The neutral safety switch … Read more
Automatic Transmissions have gotten so good since they were introduced in the 1950’s. In fact, some of them have fluid that is supposed to last for the entire life of the transmission. This often lulls people into a false sense of security. Many people NEVER even bother to check their fluid. This is a huge mistake. … Read more
Replacing a torque converter is relatively easy to do. Getting to the thing is an entirely different story. There are many reasons that you may wish to replace it. Maybe your transmission is slipping? This site is geared toward the performance crowd (well a little bit), so we are will cover stall speed and torque … Read more
Are you considering doing the LS swap? It takes a lot of work to do it right, but it’s incredibly rewarding. I’ve done this swap and there are really two important parts to the game plan. The first is to make sure that you have a game plan for all of the challenge areas. Deciding what … Read more
It’s a question that I hear about a lot. If you don’t feel like reading a long in depth article on the subject, the short answer is it depends on what they do to the transmission during the rebuild. Rebuilt Pros: The number one advantage of going with a rebuilt transmission is going to be … Read more