What gears

[Lguzman9]

I bought a 89 truck with a rear 2500 6 lug 14 bolt sf 3.73 gear recently installed but I want to know what I need to do or which gear do I need to install for the gears to be the same infront

 

[Schurkey]

If the tire sizes are the same front and rear, you need 3.73 in front to match the 3.73 in back.

 

[Lguzman9]

The same differential just need regear the gears to 3.73 ? Or do I need a new differential

 

[GoToGuy]

Since your asking , this would probably be remove the front diff', obtain seals , sealants, and front ring and pinion set.
And OE unit repair manual.
And by asking what to do, this type of maintenance may be beyond your current skill level, without some experienced help guidance. Consider it upgrade training. Good luck!

 

[Drunkcanuk]

The same differential just need regear the gears to 3.73 ? Or do I need a new differential

You don't need a new differential. Unless it's somehow destroyed. If it's working fine, you need to get a new ring and pinion set. And as already mentioned, seals and gaskets.
There are videos on YouTube showing how it's done. It's not rocket surgery, but there are some tricky aspects and specialized tools required.

 

[Supercharged111]

Much cheaper to just get a junkyard diff with 3.73s already inside. It's a common ratio, shouldn't be difficult to track down.

 

[Drunkcanuk]

Much cheaper to just get a junkyard diff with 3.73s already inside. It's a common ratio, shouldn't be difficult to track down.

This X2. Probably way less work as well.

 

[Schurkey]

Have you changed the electronics so that the speedo and odo read correctly with the new gearset?

 

[RichLo]

You'll need to remove the front diff and bring it to a qualified transmission/axle specialty shop. These front diffs are more difficult to re-gear than a standard solid rear axle.

Just let a specialist deal with all of the fine-tuning for you. It'll cost more but it'll be done correctly and usually the good shops offer some sort of a warranty period.

 

[Lguzman9]

I found a 91 Chevy long bed 4x4 differential with 3.73 for 350