No power

Hey my name is dakota I'm from western nc and I'm new on here so forgive me if I've already asked questions that's been answered but I have a 08 4.0 base model xcab 6speed 4x4 and I have the toytec ultimate coil overs up front and just Billys in the rear no lift. And it's not a squat ether lol I just had to take the add a leaf out because it was putting my carrier bearing in a bind and the shocks were too short. I'm running 285/ on stock 16s and I have hardly any power at all I mean a 4 banger can keep up with me. I know that re gearing would help but I wouldn't think that it would kill it that bad cause I have buddies with same trucks stock gearing with 6 inches on 35s and blowing me away I just can't figure it out so any help would be appreciated

 

clutch?

 

I think it's fine although I think the throw out is going bad cause it's chirping a lot and squeaking when I'm driving and sometime just idling and also truck won't go over 90mph and it just feels like when I mash the gas the motor just turning and no gain in acceleration

 

Are you up to date on your basic maintenance? When is the last time you changed the spark plugs?

 

Based on your description of what is happening, I would also suspect a clutch slipping. Of course, you have to verify you have a sound ignition and fuel system and NO Check Engine lamp ON with ANY codes.

 

Bad air pump will cause it to go into limp mode. Codes will be associated with this.

 

On 2008 4.0?

 

That's what I get for skimming. My bad. Disregard.

 

Did the 2008 4.0L have air injection?

 

Thought i missed something... it is early here

 

Yeah I'm still tired I only got like 14 hours of sleep last night

 

I just changed plugs roughly 8-10 thousand miles ago and I bought the truck with 103k miles and it's got 118k now and when I bought it the guy had Toyota put a new clutch in it

 

Verify the clutch pedal freeplay is within specification, if it's not, it can cause slippage.
Just because the dealer replaced it, doesn't mean they adjusted the freeplay, or even installed it correctly.

 

I hate going to the dealership I wished I could find someone close that knew what they were doing. But I will check on that clutch free play. And also going to work this morning and I got to about 85 steady and it sounds like something is making a ringing screeching sound under the truck any idea what that could be? Maybe my bad carrier bearing?