[Mustang SDS]

Ok, if i end up getting the gears for the stock rear end will i need the tlok to make both rear tires spin? and vice versa, if i get the tlok would i need the gears to make both rear tires spin?

I'm new at this and learning as I go. Please give any info that you can.

I was planning on getting the 8.8 rear end but money is tight now a days.

[joshw2890]

You can get one without the other. The gears just changes your ratio and if you go with a higher number than your acceleration will be better. If you want both tires to spin then you need a t-lok. But you don't necessarily have to do both. It is reccomended tho.
Also unless you plan on doing it yourself I would reccomend the 8.8. Gears and a t-lok, once you buy them and the install kit are gonna be more expensive if you pay for installation than putting in a whole new rear end. (When I was pricing them it was gonna be about 500 for an install of gears, and only about 100 for a rear end.)

[burnrubber4.0]

in the long run, an 8.8 will be more econimical. noone really has money right now to spend, but if u must have it and you want it to be reliable and whine free...go with th 8.8. its also stronger and can withstand a lot more than the 7.5. if youre like me youre not gonna be done after the gears and lock...you wont have to worry about breking down later on

[venom800tt]

As mentioned you can install either but its really a no brainer to install gear/tlock at the same time. Even with a stock 3.31 and a CAI tune you will spin the tires, now you put a gear and you wont get traction at all. Definitely put them at the same time while your cars rear end is open so you dont pay same labour twice.
Going 8.8 is wise if you plan FI but stock 7.5 is good for N/A and even FI with low psi. I got my gears/tlock on 7.5 and love it, no issue

[great08]

All my life I have heard that going higher with the rear gears is the best way to go but I have friend who has the same car I as do. When they were stock we would trade wins at the local 1/8 mile equally. I kept the stock gears, added the traction lock and an aluminum drive shaft. He went with the 8.8 traction lock, 3:73 gears but kept the stock drive shaft and he has never beaten me since. When you keep the stock gears you dont have to pull the pinion or even the drive shaft for that fact. Once you put the stock gears on the traction lock you only have to check the back lash and move the shims around from side to side to get the correct tolerance. It cost $200 to have this done and I changed my drive shaft myself. I also believe that the 8.8 adds enough rotating mass (weight that takes power to accelerate) that you will gain more by keeping your 7.5 unless you add FI. We spent about the same amount but my car is quicker and the drive shaft will stay together if I ever go over 118 mph. I will go to 3:73 or 4:10 someday but when I do I intend to keep the 7.5 and add cap studs and the TA Products Rear End Girdle.