Vigilant

Just bought a 2006 5.4 F-150 4X4 as a spare, with 98000 miles as a work truck. The only possible issue I can see is the trans. Reverse is fine. When you first crank it in the morning and shift into Drive, it goes into gear firmly and promptly, as it should. Once it has warmed up and you shift into Drive, there is a 5 or 6 second delay from going into gear, then it goes into gear fine. Had the trans serviced immediately after I bought the truck, and self-flushed with Motorcraft Mercon V. Glad I did it, but it didn't help a bit. Does this sound like a trans that's about to go, or should it be good for a few years? Thanks in advance.

650NutKase

Are there any transmission codes? How did the old fluid look when it was drained? Any metal flakes? Did you change the filter as well? How does it drive once it's in gear?

Vigilant

I don't have a code reader. Maybe it's time to buy one. Didn't look closely at the old fluid on the dipstick. Did not smell burnt. May have been a little dark. My mechanic did the work. He didn't mention anything unusual. Filter changed as well with a new Motorcraft. Seems to go through 1, 2, and 3 as it should. Grabs just a little bit going into OD. Other than going into OD, nothing seems unusual.

650NutKase

If it's driving fine, I wouldn't worry about it personally. Just FYI the BAFX is a really nice bluetooth unit. Pair it with Torque on your phone and you have a pretty good reader for under 20 bucks

Vigilant

Just bought one on Ebay, and bought Torque as well. Thanks!

Jojodapyro

Down the rabbit hole you go. So many ways to use it.

Eric Kleven

Disconnect the battery for a while and force it to re-learn?

dukedkt442

Trans is definitely shot.

Or, it’s not. Flushes suck and usually cause more problems than they cure on a worn trans. Drop .75 qt and add a bottle of Lubeguard red. It’ll get better.

edit: also pull the pan this time, clean the magnet and replace the filter.

Ecobuilder

@dukedkt442 Did a pan drop/filter change a couple months ago and got rid of a shudder while cruising at 50 mph. Been wanting to add the Lubeguard after seeing your recommendation a few times.

I'm going to perform a couple more fluid changes before adding and wanted to ask if there's much difference between the bottles that are available at my local Napa.

They have Lubeguard Platinum, Lubeguard (black bottle) - highly friction modified, and Lubeguard (red bottle) w/LXE.

Any insight or experience with these?

dukedkt442

For transmissions, I’d use the Red. They also have a torque converter shudder stop, but as you’re already seeing great results (as did I) with just 1 drain and fill, I’d avoid it. Wise in waiting to add (why lose it?). Lubeguard makes different additives for different components (transfer cases, differentials, probably even engines). FWIW, the stock 2004-r in my Olds has lived its 140k miles behind a 307, a 10second turbo-455, a 312 and now a SBO 350 without any major issue, except a cracked TC (from decades of abuse) and has had LG since the 90s. Yeah, I’m a believer in the stuff.