swapping gears

[myC-dime]

Hey guys, kinda new here and need some advice. I have an 85 stepper with 350/350 combo and 2.73 gov.loc rearend. I would like to do some towing say around 4000-5000 lbs. What gears do I need ? Do I have to change the carrier as well? I may swap in a 700r4 latter. ANy help would be appreciated. You guys really know your squares.. Thanks

 

[bucket]

3.73 would probably work well. Will you only be using the truck for towing? What size tire do you have?

 

[MrMarty51]

Leave them gears alone,the 700R4 should not be towing in overdrive,it`ll take them sungears right out.
I have a 93 1500 GMC 350 700R4 and had to get the transmission rebuilt one time when I was almost to My Brothers in G.V. california.Took it to Red E trans shop in Citrus heights,they opened up some lube riflings to them planataries so I wouyld not have that problem again,they also told Me to not tow in O.D. so when I hook onto the trailer it is in drive only,a bit slower,a bit better on fuel and that trans has over 150,000 on it now,it does not slip and it shifts flawlessley.
I like them taller gears for when I am not towing.thats all.LOL

 

[myC-dime]

Won't be used strictly for towing , want to drive it around town as well. I probably wont take it long trips in it. If i swap to 3.73's do I have to change the carrier as well. A little scared to tackle this myself, But I want the knolwedge so I don't get screwed..

 

[MrMarty51]

Won't be used strictly for towing , want to drive it around town as well. I probably wont take it long trips in it. If i swap to 3.73's do I have to change the carrier as well. A little scared to tackle this myself, But I want the knolwedge so I don't get screwed..

Just be sure to order the gears for the differentials that is under it,there is a lot of nice combinations for gearing and a lot of different brands.I dont know which brands might be better or worse than the next.

 

[crazy4offroad]

Should be 2 carrier breaks, 3-series and 4-series. 3-series includes 2.73-3.73 gear ratios, 4-series is 4.10 and up. When you go with the 700R4 be sure to add on a secondary trans cooler, and when towing shift the trans into 3rd instead of overdrive to reduce the strain on the trans.