Dude... you have been talking yourself out of buying these in this whole thread. Dont do it. If you really felt good about it, then you would have already pulled the trigger. Instead of dumping the $600 on something you dont really want, give it to somebody you trust to hold it until you can scrap up another $600+ and get your 37's.

I am also pretty surprised to hear you worried about your rpms's with the 5.13's. Havent heard that complaint from too many people. FWIW, I share the opinions of Bigblue and prefer a 37/38 as the largest tire that looks good on a JK. Of course, just my opinion and not trying to be insulting to anybody...

 

Someone on here has broken 2 D44 axle shafts with 40s, so I would also be concerned about your D30 breaking....

 

i wouldnt do it...i know its a GREAT deal that you probably would never see again,but i'd either put it aside and save or use it like you said for something else useful that you really want and would enjoy instead of dealing with the breaking/fixing method...that would just be a freakin hassle....and i think your jeep already looks sick as hell...i dont think it needs 40's at all

 

If you can get these for $600, and they sell for $2400 (all four), why not buy them, sell them and your 35's, and get the 37's you want and a little cash in your pocket???

 

Heck, I broke two D44 CM shafts on 35's. I can't even conceive of a 40 on a D30.

 

Looks like you've already made your decision, but I'll comment on the above remark.

A deal is only good if it makes sense in the grand scheme of things for YOU.

The other option, as I think someone already mentioned, is to buy them and flip them for more $.