Gear down for 31 inch tires?

I have a 1998 tacoma extracab 2.7 4x4 with 31x10.50's. I was just wondering, since stock tire size was 225/75/15, has anyone tried gearing down when they went to 31's? I know that the larger size reduces RPM's and is a little extra weight to sling around and I was just wondering if I should try to do a gear swap. Thanks

 

Were those 225/75/15 factory? That calculates to a 28" tall tire. My 90 toyota pickup came factory with 30.6" tall tires. Either way unless you do some serious offroading you will be fine with your factory gear. Assuming it is a 3.73 or shorter.

 

Ok I looked at my factory sticker and it tells me that I have an 8" 2 pinion open rear end with 3.58 gearing. Sounds a bit high to me. The sticker also says that the stock tire was indeed 225/75/15.

 

Well then if you really offroad alot, I doubt that you do seeing as how you have an open diff, and need the gear yes definately get new gears. Your setup now will translate to a 3.25 gearing. I'm surprised to see such a short tire on a 4x4. Being a 4x it makes gear swaping expensive. If you decide to go that route a 3.90 gear or the negibhorhood of will put you back close to factory. However if you are changing your gears and want a little more installing 4.10 gears will make your truck handle like it has 3.70.

 

I mainly do highway driving and a lot of around town. I've just noticed that I lack power in 5th gear. If i get into 5th below 60 mph the truck shakes as if it is underpowered in that gear. Just trying to figure out if I've got the optimal gears.