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Calling all EXPERTS!

Bronco_007

Contributor
Jr. Member
Joined
Mar 14, 2022
Messages
59
Loc.
Nature Coast, FL
Yes, that means YOU! You’ve just been promoted to expert!

I need advice…

My baby blue is a 1974. Stock 302, stock three on the tree. 235/85R16 KO2s (31.7/9.3). It has stock 3.50 gears.

I’d like to re-gear front and rear and will likely update the tranny in the next one to two years. The engine stays, it only has 66k miles on it. With a rebuilt original carburetor.

I spend 75% on road, 25% off road.

The age-old question presents itself: what tranny and gears for my engine and tires?

I’m thinking 4.11 front and rear with a Detroit Trutrac in the rear. And I’ll likely go with the AX15 in the future when I make a big transmission swap or have to do any major maintenance on it.

EXPERTS, opine!
 

Timmy390

Bronco Guru
Joined
Jan 1, 2011
Messages
5,285
Loc.
Conway, AR
4.11's with Truetrac in rear, 33's and just went M5ODR2. Couldn't be happier. 95% street and it's great. Overdrive is VERY usable on the back roads just cruising.

In no way saying my combo is the best as everyone likes what they like but I'm super stoked about my setup.....I do bump a 351W with a torque cam, good heads and EFI. I'm sure that helps my combo become one with the Force........

Tim
 
OP
OP
Bronco_007

Bronco_007

Contributor
Jr. Member
Joined
Mar 14, 2022
Messages
59
Loc.
Nature Coast, FL
4.11's with Truetrac in rear, 33's and just went M5ODR2. Couldn't be happier. 95% street and it's great. Overdrive is VERY usable on the back roads just cruising.

In no way saying my combo is the best as everyone likes what they like but I'm super stoked about my setup.....I do bump a 351W with a torque cam, good heads and EFI. I'm sure that helps my combo become one with the Force........

Tim
The Force is strong with us, Tim.
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,879
I have 33" tires with 4.11 and if I had your truck I would do it all over again but I use a detroit soft locker in the rear and a tru trac in the front. since your in Florida you have no snow to deal with. so you can add traction aids. at minimum I would do tru tracs both front and rear. with 4.11 you can use thick cut gears in the front so you don't have to by a new carrier for the gear split. At the rear if you changing the carrier to a tru trac then you have to decide if your running the stock 28 spline axles or upgrade to 31 spline axles I personally have my stock 28 spline axles running the Detroit soft locker and an automatic transmission for over 20 years. just depends how hard you want to play and what risk's you want to take.
 

Timmy390

Bronco Guru
Joined
Jan 1, 2011
Messages
5,285
Loc.
Conway, AR
I did upgrade to 31 Spline rears after my factory limited slip split in half. That was just after my W went in and I was running 32's at that time. I have a Dana limited slip up front.

Tim
 

BOBS 2 68S

Jr. Member
Joined
Jul 26, 2015
Messages
166
Loc.
Hudson, CO
I am running a Blue Print 302, Holley carb AX-15 trans, 4:11 gears and stock sized tires. Very happy combo. Just pulled my 1970 Cardinal camp trailer camping and fishing over a 10,000+ foot pass and got 13.14 mpg
 
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OP
Bronco_007

Bronco_007

Contributor
Jr. Member
Joined
Mar 14, 2022
Messages
59
Loc.
Nature Coast, FL
I have 33" tires with 4.11 and if I had your truck I would do it all over again but I use a detroit soft locker in the rear and a tru trac in the front. since your in Florida you have no snow to deal with. so you can add traction aids. at minimum I would do tru tracs both front and rear. with 4.11 you can use thick cut gears in the front so you don't have to by a new carrier for the gear split. At the rear if you changing the carrier to a tru trac then you have to decide if your running the stock 28 spline axles or upgrade to 31 spline axles I personally have my stock 28 spline axles running the Detroit soft locker and an automatic transmission for over 20 years. just depends how hard you want to play and what risk's you want to take.
I’ve not heard of the soft locker. I’ll look it up!
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,879
I’ve not heard of the soft locker. I’ll look it up!
its just sprung a little differently so its not as harsh locking up virtually no banging into lock up unless you throttle around a tight corner. a lot better manners. I also put one in my 4 cylinder tacoma pick-up it wasnt as midley mannered. may be truck was too light?
 
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