2005 F150 Lariat 5.4 v8 automatic transmission. 102,100 miles. Transmission will slip or quiver between 40-50 on acceleration on a slight incline. And beginning to quiver at same speed upon decelerating. What is going on? Can I add Lucas transmission fluid to stop it or is it going bad? I don't pull much with it at all. I watched a YouTube video saying Ford changed from metallic balls to plastic and causes pressure problems as they wear. What is going on?
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have a transmission specialist look at it
Can I add Lucas transmission fluid to stop it or is it going bad?
Too often, misfiring and a poorly running engine (lack of power) is mistaken for a failing transmission. Many just assume that "no go" automatically means "slipping", which isn't the case at all.
This is one of the many problems of being an internet mechanic. People will tell you their diagnosis (which they guessed without testing) and expect you to tell them what part to replace, or additive to pour in, even if it's completely unrelated to the actual problem, instead of starting at the beginning and giving you a detailed description of the symptoms and asking for advice. (not you personally).
🤷♂️
Anyway, it's a good thing you have a common sense mechanic who starts with simple stuff first.
What is going on?
Your 18-year-old transmission is probably wearing out. When is the last time fluid and filter were changed? What is the fluid's condition? Is it at the correct level?
Can I add Lucas transmission fluid to stop it or is it going bad?
Lucas additive would be a temporary bandaid at best and may not work at all. It cannot repair a worn-out transmission.
Your truck needs to be evaluated by a transmission expert.
Age shouldn't be a problem due to low miles. Bought with only 46k miles. Yes fluid changed at Ford recommended mileage. My mechanic says it should last 200k miles. It's always serviced appropriately.
Age shouldn't be a problem due to low miles.
Incorrect. Age takes its toll on seals and other components.
My mechanic says it should last 200k miles.
I guess he has a crystal ball. What does he say about the symptoms you are experiencing?
He knows customers that have gotten that many miles! Why do you think he has a crystal ball? He prefers GM or Chevrolet transmissions to work on. He thinks it could be electrical since no problems st highway speed.
I bought a 1973 Plymouth roadrunner and 2 years later it was rolling downhill at a 7-11 I was at. Got it rebuild at AAMCO with lifetime warranty. It's still in there today still working. Have it checked every year. Only drive 500 miles a year since it has antique plates. They haven't changed fluid in years. How many years is my roadrunner now. It's old, more so than my Ford. When my mechanic in my home town repairs transmissions, he uses Lucas transmission fluid to last longer. So I'd like Scotty to chime in on the known transmission problems with my Fords year.
I have cars from the 1960s with automatic transmissions that have lasted decades. They are simple with 3-speeds and are hydraulically-controlled with no electronics. You're conflating transmissions built in different eras with different materials and different levels of complexity and overall durability. A Chrysler Torqueflite 727 is more robust than almost anything in modern vehicles and is also much simpler. Doesn't even have a lockup torque converter. An ambitious home mechanic can rebuild one of those at home.
Lucas is snake oil but it probably won't harm anything. It's up to Scotty what issues he responds to, he cannot respond to them all. There are instructions in the FAQ for contacting him directly if you want to give that a try.
The person here who probably has the most specific experience and knowledge of a wide range of transmissions is moderator @dan. Perhaps he will chime in with more detailed information.
He knows customers that have gotten that many miles!
Some people get that many miles out of them, some do not. 200K is actually not all that unusual or impressive, I've gotten over 300K miles out of automatic transmissions and others have certainly reported more than that. (Too many variables to predict the life of any one specific unit though - unless maybe one has a crystal ball.)
It could of course be an electrical, solenoid, or computer module problem. It could even be torque converter shudder causing the quivering symptom. As I said you need a transmission expert to diagnose it. On a computer controlled transmission they'll use a high-level bidirectional scan tool to analyze what's going on. (Note that if it is an electrical problem the Lucas additive you mentioned will certainly not help.) If you continue to let that transmission slip even if it is an electrical problem at the moment you'll wear out friction materials so get it diagnosed ASAP.
Had a transmission shop put a $5000 scan tool on and found nothing wrong with transmission. He said I need to change my Autolite spark plugs with Motorcraft plugs. Got 50,000 miles on them. He test drove it and felt quiver between 40-50 mph. New spark plugs should fix it!!! He was very confident about it! Will get that done and update here after it's done.
That means that the transmission must not be slipping after all. Very fortunate since slipping usually means transmission death. If it's the spark plugs then the the "quiver" would be the engine stumbling. In any event if it turns out to just be spark plugs, buy some lottery tickets while your luck holds out!
Can I add Lucas transmission fluid to stop it or is it going bad?
Too often, misfiring and a poorly running engine (lack of power) is mistaken for a failing transmission. Many just assume that "no go" automatically means "slipping", which isn't the case at all.
This is one of the many problems of being an internet mechanic. People will tell you their diagnosis (which they guessed without testing) and expect you to tell them what part to replace, or additive to pour in, even if it's completely unrelated to the actual problem, instead of starting at the beginning and giving you a detailed description of the symptoms and asking for advice. (not you personally).
🤷♂️
Anyway, it's a good thing you have an honest, common sense mechanic who starts with simple stuff first.