3.40 ratio and tire size

[wazzabie]

What is the largest tire size recomended for the 3.4 ratio 12 bolt and dana 44 front? Where these a common ratio in K5s in the late 70s?

 

[K85 Octane]

whats the trans?

 

[4xcrazy]

i had 3.42 stock in my '89 Burb when i got it, stock size tire was a 31" with the 700r4 trans. Was a decent combo, got decent fuel mileage for a rolling brick down the highway.

 

[imiceman44]

What is the largest tire size recomended for the 3.4 ratio 12 bolt and dana 44 front? Where these a common ratio in K5s in the late 70s?

It was common in the late 70's and early eighties.
If you have the stock 350 and th350 I wouln't go with more than 33"
If you have a manual or if you have a healthy engine you might be able to swing a 35".
I have seen bigger tires on that ratio but they are dogs, plus you could easily kill the axles with bigger than 35" tires.

 

[wazzabie]

th350 is the tranny. i swapped out the np203 for a np205. This combo and 3.4 ratio axels are going to need to do for now. I'm considering a 4in lift with either 33 or 35's. long term goal (maybe 2-3 years from now) is 1 ton gear/ 4bt swap. The stock engine is tired... it has 140K on it but still some life left.

Maybe I should just go with 31s then and wait till I get the axels and 4bt to swap. Rather the a 4in lift I should go with the 2in for now.

 

[shovelbill80]

a granny 3 with a 35 would be like having overdrive.....and still pull like a bastard of the line.

 

[shovelbill80]

also, if you wait for 1 tons you won't have to buy tires twice.....

 

[COCHEV]

its an economy ratio, but better than 3.08s in my opinion. with 3.42s, 31s, tbi 350, sm465 i get 14 mpg...

 

[tRustyK5]

I'm running 3.42's with 35's and a 700R4. Around town it's fine, but on the highway it's pretty doggy. Any grade and it drops to drive...hell I could realistically never use OD with this combo. Mileage is about 12-14.

Rene