It's the harmonic balancer puller. It would be quite a task to do it without it. I'll let you know.

 

Sounds pretty technical and since all I really know how to do on my truck is just regular maintenance I might be better off letting somebody else do it instead of me messing up something lol.

 

It's a very simple tool but necessary for removal. Any manual can walk you through it. You can rent it from Autozone.

 

so i want to be clear. as far as the butt dyno is concerned... is it worth it? very noticeable gains?

 

Well, the consensus is that it works. I did a few things at the same time so I honestly can't say that I felt the UDP alone because I didn't do it by itself.

 

Ray, did you have to replace your alternator on your truck to a bigger one after installing the UDP? I'm just making sure the stock 95amp (I think that's what it is, b/c I can't find the rating sticker on it) can handle running everything after installing a pulley. I definitely don't want to blow my computer or something.

 

I used the 130 amp alt from an Explorer before because I'm running an electric fan and am running an amp. Low voltage won't blow a computer. At least I've never seen it happen.

 

Alright. I have the stock fan and no stereo except for an aftermarket radio and speakers with no amp. So in theory I should be good to run the UDP without having to upgrade to a 130amp alternator. Sorry to be such a bother man. I just want to make sure that when I install this deal I won't have any problems in the future such as not having enough electrical power.

In case I do need to upgrade the alternator, what year explorer did you get your 130 amp alternator out of? I suppose it would have a 4.0L SOHC in it? And did it completely bolt on with no problems?

 

Low voltage effects fuel components, which will change your fuel trims.

 

Ok, so if it affects fuel trims, will that be corrected with the addition of a larger amp alternator? I do have an X3 that is programmable, can I use it to correct the fuel trims? Sorry, I don't know anything about electronics. I work primarily on older cars with my granddad that don't require all these things to think about when trying to beef up the engine, if you can call giving 10+ HP "beefing" lol.

 

You can either run the bigger alt or run an overdrive pulley on the alt. I forget which model the alt comes from but there should either be the optional one or it may just be the standard one. You can tell be looking at it. It's much bigger than the 95 amp.

 

Ok man thanks. An overdrive pulley on an alternator can prob be found at local parts place right? But then I'm worried about running the alternator too much and cause it to burn out. It already has 101,000 miles on it now. This Friday I am going by the performance shop and see if they can't run their dyno on my truck to see if I put an underdrive on it, will it still be pushing proper amperage through the system and not let the a/c get hot etc, etc.

 

The overdrive will just bring the alt speed back up after the UDP. It won't spin any more than stock did.

 

Oh ok I gotcha. I think it is all questions, for now lol.