Since I have switched over to a Superchip from the diablosport, the 1-2 shift is MUCH firmer. At 3/4 to full throttle, it literally snaps immediately into 2 for a nice little jump forward. Problem is, there is a small amount of slippage when the shift occurs and I get what sounds like a belt slipping during the shift. Is there anything I can do to fix that issue? Synthetic fluid? Adjustments?

Ken

 

I've noticed occasional belt slippage on 3/4 and higher throttle at times depending on the weather mostly. I would imagine that's all you're hearing. Probably nothing to worry about.

 

Well, i'm glad to see some of us are taking advantage of the 5.4L's. Mine does it all the time (Cuase I full throttle my truck a lot. Prob more than I should). If you're really concerned, you may want to tighten the tensioner for the surpentine belt. You just unbolt the bolt to loosen the tensioner, tighten it and retighten the bolt. I'm (1) too lazy to do this and (2) stupid enough to buy a replacement belt more often than normal.

If I were you, I wouldn't sweat it.

-Joel

 

Hi Ken800,

As the other posters have already mentioned correctly, it's your serpentine belt slipping, not anything in your transmission.

It's simply from the shift being so much quicker at full-throttle. The shift isn't abnormally harsh, it's a quick, firm and positive upshift, just as it should be at WOT (wide-open throttle).

It can be cured a couple of ways, do the adjustment to the tensioner, or you can use some belt dressing, or just replace the belt. Your belt will stretch over time of course, and it also has to wear the paint off of the various pullys (I know, it's "pullies"), and that can cause less adhesion between the surface of the belt and the ribbed surfaces on the pullys, etc.

This is easy to take care of, and your transmission is just fine.

 

Where is the adjustment? anybody have a picture?