Tune or gear swap.

[metaljunkie]

Which is a better bang for the buck if you had to choose just one. A Black Bear tune or a switch to 3.73 from 3.42.

 

[Jerky Arm Ape]

Depends on the goal?
What are you trying to achieve with either?
Larger tires or adding some go fast to a street machine?

 

[metaljunkie]

Daily driving and towing. Stock motor, exhaust and tires.

 

[ccapehartusarmyINF.(ret)]

how much towing and what kinda load
go for the 3.73 a tune is going to give you a little fart for alotta buck
increasing yer rearaxle ratio increases torque multiplication
more power off the line little less top end speed say for example with a 3.42 yer rpms are at 2000 at 75 mph with a 3.73 you mite be at like 2500 rpms at 75 mph

 

[metaljunkie]

That is what I thought. I see a lot of people talking about how great their Black Bear tunes are, I figured I ask. I don't know if swapping from 3.42 to only 3.73 is really worth it in a 4x4. Thanks for the reply.

 

[Jerky Arm Ape]

Agreed, I feel you will benefit more with a gear swap in your situation and for what you are wanting.
3.73 will help you some, if you have to buy new ring gear and pinions plus install kits, I may would look into a different gear ratio versus buying some used running gear off of a different tahoe/yukon with the factory 3.73 gears.
Although if you go much lower, you may end up with a single purpose vehicle that is only feasible for towing versus daily driving, rpms would run quite high, even in over drive.

 

[TheAutumnWind]

IMHO Tune. You'll increase MPG and power.

Gears are a tradeoff, as highway mpg will suffer.

 

[Jerky Arm Ape]

Vehicles designed around/for towing & hauling typically have lower gear ratios.
Think half ton vs. 3/4 ton.
Adding power to the engine will really labor your trans when towing with the higher final drive ratio.

Also, as previously stated, lower gearing will cause higher highway rpms and cost mileage and engine life.

3.73 did come equipped as an option from the factory with 245/75 tire size so it isn't going to cost you so much on the topend that it will ruin the highway capability of your vehicle.

Ultimately, the OP will have to decide what's best for your vehicle and pocket book + your personal skill set as far as the gear swap is concerned, unless your paying some one to install which goes back to the pocket book.

Maybe you should do both.

 

[ezdaar]

If you do a gear swap, get a low mileage rear end from JY (Cheap) and swap it yourself.
Then pay to have gears swapped in front end, or do it yourself.

Either way, you will need a tune as your speedo will be off..
Use the $ you saved by doing a JY rear end and not a gear swap to pay for BB tune..
If done right, you should be in it for aprox 700$

150$ 0r less, used pull out rear end assembly. If less, add to cost of front end gear swap.
300$ BB tune.
250$ for a gear swap on front axle.

Noticeably Improved Everything! Tow, Mpg, power. etc..


GL

 

[metaljunkie]

A earlier post got me wondering. In older carburetor vehicles I always ran 3.73 or lower depending on lift and tire size. I've always been a fan of lowers gears. I've never had a tune done so was not sure what to expect.