Knowledge, Read this it could save you lots of $$$
This page is intended to give you the customer some inside information on the do's and don't(s) of vehicle operation. Plus some knowledge of how to tell if your vehicle has a problem before it ends up costing big money. This will also give you some firepower when taking a car to get serviced by asking the right questions.
Do's and don't(s)
1. Tire Size
Automatic transmissions and transaxles are smarter than ever, the computer takes into account the tire size to not only determine vehicle speed but, shift timing and quality. In Front Wheel Drive vehicles tire size is crucial to the operation of the transaxle. Two different size tires on the front drive wheels causes a gear ratio difference inside the transaxle. Basically one side of the differential spins faster than the other. This causes premature wear and ultimately transaxle failure. Different tire sizes on a vehicle include: different brand names, one tire being older than the other, or the donut spare being run on the front too long. Front drive tires should always be replaced at the same time. Never mix the brands they could say on the tire that they are the same size but, on most cases they are a little different, even tread height can be significant enough to cause a problem! The donut spare is intended to keep you from getting stranded! If you look in your owners manual it tells you to go immediately to a garage to get the tire replaced. THE DONUT SPARE IS NOT A PERMANENT FIX!
4 Wheel Drives and all wheel drives should have the same tire size all the way around!
2. Towing
A vehicle should NEVER be towed with the drive wheels on the ground! When the engine is not running the internals of the transmission is not getting lubrication, basically causing the transmission to melt down. I have seen transmissions completely melted in half due to this and can also cause the vehicle it self to catch fire! 4Wheel and all wheel drives should be flat bedded.
How to tell if you are experiencing transmission trouble.
1. The Check Engine Light
Hearing people come in over the years and say that a shop told them not to worry about the check engine light makes me very frustrated. The check engine light is your friend. its a general warning that tells you something is wrong. The check engine light warns of more than just engine problems it is tied into all the computers on your vehicle. What does this mean? Any thing from the gas cap being loose to an internal transmission failure can cause the light to come on. Computer Diagnostics is the only way to properly diagnose a vehicle after 1990.
The Overdrive light
On some vehicles, mostly Ford, there is an Overdrive cancel light to tell you that you are out of overdrive. However when the light starts to blink and usually accompanied by the check engine light, it means there is a transmission problem, and should be taken in for diagnostics ASAP.
2. Trouble Codes
The first step in diagnostics is getting the codes that are stored in the on-board computer that caused the check engine light or overdrive light to blink. This is the easiest step, and one most off the shelf scanners will do. However since there are usually more problems than codes stored in the computer most codes have multiple meanings and the same code can be thrown for more than one problem. Also some codes can cause other codes to be set. This is where diagnostics gets tricky, due to just being in the business for so long and expensive troubleshooter software you don't se in off the shelf scanner, we have come to recognize some of the patterns of codes thrown as a particular problem. This is not always the case. Some vehicles my take several days to diagnose, especially when the problem is intermittent or the computer is not detecting a problem and not throwing a code at all. For example: when ford Manual Lever Position Sensors(MLPS) go bad, the transmission ether quits shifting or shift hunts. Sometimes they throw a code and sometimes not. It depends on the computer. This is why computer diagnostics is so crucial. I have seen many times people come in and say "I need an overhaul because my transmission won't shift." We diagnose it and fix a $200.00 MLPS instead of a $2000-3000 dollar overhaul.
3. Transmission Leaks
The fluid is the life blood of your transmission. The fluid in an automatic transmission does 3 things: Lubricates, Cools and provides hydraulic pressure. This is why the vehicle may not move when it is run low on fluid. Transmission leaks no mater how small should be taken care of immediately! You could damage your transmission just by running it low on fluid once! Transmission fluid should be changed around every 20-25,000miles. Some signs of running low are: Slipping, Dropping out of gear, Neutral at stops, No movement, Whining noise.
