yea thats why im showing 70 and300rpm.im gona try to buy the gears over time.i think im going with 4.88's.what will the top speed be?would you put 4.56 or 4.88?i dont think ill ever go bigger than 33's.will it still have power?my frends yj has 35's with 4.10's and hasnt used 5th in years.will my 5th pull decent.i realy want to goahead and upgrade the axle shafts when i regear but its gona take months of saving for all that.thanks for yor help  

if...you could get it to rev to 5500 rpms with 33's and 4.88's in 5th gear the top speed figures out to be 130mph!

now thats a scarry thought in a TJ with big tires.  

yeah, asuming you have 4.10 gears stock and 30" tires...the 4.88's will pull the 33" tires about the same as the stock gearing and the stock tires did prior to the tire size change..

2537rpms w/4.10-30's @65..
2745rpms w/4.88-33's @65, the 4.56 will fall a little short from the extra rolling resistance of the big tires.  

thanks for all your help.ive got a question about spider gears in my cusin's tj in driveline.i think you realy no what your talkin about so check it out if you wana and tell me what you think.thanks  

hey mudb8 thanks for that info, im exactly in the same situation, i just got a 98 tj 4cyl and im looking to get 33's on it, i've already got a 2 inch suspension lift and im thinking of getting a 1 inch body lift, my plan is to get a rubicon express 3.5 superflex on it, but it'll have to wait 8 months or so....

i've been worried also about the gears; Where did you get the info or do you know about a chart to calculate the speed with the gears?  

Don't know if this is the same one mud uses, but this one came from Quadratec.....

 

my old 2000 tj which is now my brothers jeep (which is the jeep i created my screen name about: fastjeepwrangler) will top out right at 115mph and 5100rpms (right on the red of redline) in 3rd gear. its a 5 speed 4.0. it has the stock 3.07s in it and 31 inch rubber.  the mods he is running is a K&N  cold air, a polymer tb spacer and a magnaflow exhaust. it can hold its own in races i wont lie, but its geared so high 5 gear is barely drivable.  mud dont throw up the flag on the 115mph.  

na..actually acording to my calculations the 3.07, ax-15 and 31" tires comes up to 179 mph @5000rpm!

and the third is closer to 100..thats on paper!

anyhow heres my favorite ratio/tiresize calculator...

http://www.grimmjeeper.com/gears.html  

how much lift will fit 35's with no rubbing problems?would the 4.88's pull them?  

4.88's are ok, manufactures recommend a 5.5-6" for 35's,
although 3" lift will work without rubbing as long as the swaybar stays connected. longer bumpstops will need to used and possibly some trimming to the rib the flare connects to on the underside of the fender especially if you intend to disconect the sway bar for more travel

to keep the tires from contacting the spring tower when fully articulated, (no sway bar) 3.5" backspacing is needed w/12.5 wide rubber.