thinking about purchasing ASP underdrive pulley 2 pc. set , part #527374 which is the 6 rib for 2003 5.4L. does anyone have any personal experience with these ? any pro's and con's are welcome. thanks- jay......

2003 F150 FX4 --- 44k miles
FAL electric fan kit
K+N intake kit
Superchips #1715 tuner
Gibson cat-back exhaust SI/SO
AMSOIL 5w20 with Motorcraft filter
Optima red top 34/78
Scangauge II
Firestone Destination AT's 265/70-17

 

Your going to see a broad spectrum of opinions on UDP's... some will say go for it, other will say its not worth it on the heavy trucks.

On my mustang, I absolutely love my BBK UDP's, and I can't see anything bad about adding them to my truck. The way I look at it... anything that adds power (even if only a little bit)... is adding power.

You'll notice your lights dim at idle sometimes, but nothing crazy. You should notice some more pickup on takeoff as well.

 

I got pulleys on my truck but they are the MAC pulleys. I say read up on them then pick what you want.

 

id go with at least a 3 piece set. crank pulley, water pump, and alternator.

havent heard anything about ASP. ive only heard good about MAC though.

 

the reason i am looking at the ASP brand is that unlike the MAC or BBK models, the crank pulley is a one piece unit crank/balancer pulley, not a "piggyback" type that attaches to the stock balancer.
thanks to all that have chimed in--- jason

 

Do a search on the topic to find more info. I was sold on the ASP pulleys due the piggy back required with sets like MAC which I have and BBK but I read a post by a Ford Tech who has the MAC pulleys. Some of the crank pulleys of the sets that replace the crank pulley have worn down over time and caused the motor to knock. The piggyback using the stock crank pulley is sound as long as things are tightened well. The stock crank pulley has had very few problems over time.