May well not be your crank that is creaking. Like @kiwisimon said, do a google search as there are checklists to go through. I once thought my crank was creaking. It turned out to be the front wheel skewer.
Regarding BB grease, if it is a PF BB, Wakos make a really good grease. The mechanic at Y's road told me he heard about it by going to a cannondale seminar on creaky BBs. They recommended the grease. I can't remember the name but @TCC may be able to help.
For a while, I had what I thought were creaky cranks on my old bike. Then I moved them on to my new bike, and now my old bike (with different cranks) doesn't creak and my new bike does.
It can't hurt to grease up my cranks, and I don't have any grease anyway, so I think I'll buy some and see what happens.
Good to hear your bike has stopped creaking @leicaman.
It's mighty irritating.
As @leicaman correctly states, the creaking may not be coming from your cranks. You may get lucky and fix the problem by applying grease to a certain part of your bike that you think might be the source of the noise, (in this case the cranks) but a better and more systematic approach would be to locate the exact source of the noise using systematic analysis, and not guess work, then take the appropriate steps to deal with the issue.
So, given this, and given that you are saying you have a creak from your cranks, lets go through complete process of fixing this, as follows;
1. Questions, and instructions, and feedback from you, which will lead to an accurate and correct diagnosis of the problem (ie, the source of the creaking).
2. Analysis of the cause of the creaking.
3. Removal of the problem by whatever means are necessary, leaving you with a silent bike.
This is the only way to deal with a problem with your bike (or any machine, or system) that will work 100%, so when you are ready to begin, post here and we can get on with it.
Once I had some creaking, took it to the shop and they couldn't find it. After an hour or so of several people spending time on it, the shop owner came over and (thru experience or chance) happened to notice the my rear skewer was not tight.
You asked for advice on a product which you considered appropriate for a problem you were having. 4 people commented that your issue might not be solvable with the product you were considering.
You ignored this, and also the offer for deeper analysis which would have found the source of your problem, and just ordered 'some grease', essentially making the whole thread pointless. Feel free to ask for help in the future. Hopefully there will be members willing to give it to you.
The usual suspects have been covered above (improperly mounted BB, and/or crank arms, wheel skewers (?), etc.). Often what you think is a creaky crankset is actually something a little higher up the seat post tube. You think it is the crankset because every time you exert pressure one pedal or the other, often at a certain point in the revolution, you hear and perhaps even feel a creak. However, the real problem is often an improperly seated seat post, improperly affixed seat post bracket, and/or an improperly secured saddle on the post clamp. I would work my way down from top to bottom there. Next, I would look at the headset, and make sure there was absolutely no play there, and that the stem/post/handlebar were all tight and secure with no play, but smooth movement. Pretty sure simply applying grease to your crankset, though, is not the solution (unless it was improperly set up in the first place). Good luck!
Even if it seems you don't have interest in the solution of creaking bb anymore but rather on brand of grease, ill share my experience with creaking BB anyway.
I have the same experience as with the other who advices it might not the BB is creaking. Once i rode and rain poured and I still rode so everything went soaked. And then i started hearing this annoying sound that i suspected coming from the cranks area. Upon arriving home i washed my bike and tested if it the noise is still there unfortunately its still there so i immediately cleaned and regrease it and tested but its still creaking. Until i remembered during the ride i checked and tightened my skewers front and rear. So i change my wheelset to my other set and viola! No creaking anymore!
I have a…. Well, I think it's a clicking shoe or pedal, so I'm going to buy new shoes. I've been told it sounds like a loose chain ring bolt. But to me it sounds like a Fecking annoying (Insert anything you like). So I'll start with those two places and if that doesn't fix it i'll start smashing random things with a hammer.
Was a skewer for me, too. Sloppy skewers poorly tightened had me thinking it was a BB problem when it wasn't. I had it replaced for good measure but that didn't do the trick. Pay attention to them skewers!