gears?

[mothertrucker424]

what gears are ya'll running and what size tires?

i have stock gears and 33's and its killling me when i let off throttle
i would like to see what ya'll run or what a better set-up would be i would like to run 35's also but not till i re gear
and what ya'll using for lockers?

[1969k10stepside]

I have 3:73s on my shortbed with 35s.The 69 has 4:10s.4:56s are good for offroading but I wouldnt recomend them for a driver,unless you never exceed 70mph

[DirtyLarry]

Just last year I stepped up and invested in gears and lockers in my ’78 K10 w/3/4 axles. Next to the big block the gears and lockers have the best upgrade yet. The front locker (clutchless limited slip) is a Detroit TrueTrac while the rear is the typical Detroit Locker.

I am running Q78 x 16 Super Swamper TSL’s (~35.5 x 10….tall skinny suckers) with 4:56 gears. It made a heck of a difference going to the 4:56 gears from the original 3:73 cogs. You almost have to relearn how to drive your rig with a Detroit Locker in the rear if you have decent HP under the hood, as the ass-end tends to steer itself as you monkey with the go faster pedal. I could see this thing being an issue to drive in the snow and ice if it was my daily driver.

I think for most people 4:10’s are perfect for the 33 – 35 inch tire crowed as well as a TrueTrac limited slip for the rear. My 4:56’s feel a bit tight on the highway but come alive when I hit the mountain trails. Just need OD now so I can do a little more than 70 MPH on the highway without getting 3 MPG and the fat rat sounding like it is about to make 8 big dents in the hood. Sure glad I didn't go with 4:88's.

[1969k10stepside]

I will also throw in that if you want to upgrade to bigger axles,you could get a 14 bolt rear and a d60 front,those arent needed unless you are a off roader,they arent just for the hard core off roaders...just somewhere in between Good luck if you want to upgrade to a d60 front.They arent cheap,or easy to find.14 bolt rears are though,they are fairly cheap

[DirtyLarry]

Amen to that Dustin…..I cannot find a front 60 to save my arse although I believe I can build my 44 to be as strong as a 60 being that I am into slow trail riding more than skying the front end. I live close to Ft Carson in Colorado Springs and every time I find a decent auction on a CUCV those &^%$#@ at Boyce Equipment snap them right up. Well, we think it is them that are buying up all the good military stuff anyway. I have a solid lead on a front 60 out of a 80’s F350 but it is a left side pinion. That won’t do me any good except trading power….unless I SFA my 2001 Silvy HD, which is unlikley. It is a 49K mile cream puff that hasn't even left the house since December.

[1969k10stepside]

You could be like Kurt and run a ford axle.A d60 is a d60,unless you refuse to own a ford part on your chevy.I seen a military blazer the other day.I drove right pass,it slipped my mind till I got home it probably had a d60 front,I dont think it was 4 sale anyway.I am hoping to find one saturday in the junkyard.I guess I better keep dreaming

[DirtyLarry]

Yeah, I have a way too much GM blood running through my veins (well, a little bit of Chrylser & Toyota too) to use a Phord part on my junk. I would consider the left pinion 60 for my Silvy HD though…...after all, it is really not a Phord part per’se …it is a Dana part made to fit a Phord. Well, at least that makes me feel better knowing that.

A Dana axle in a Phord truck is like a diamond in a goats ass anyway. Too bad the late model GM front axle stuff is all AAM IFS crap. Dodge too...I don't know that they were thinking when they ditched Dana for AAM products in their SFA 2003 2500 and 3500 4 digger Rams. Although, AAM now owns the rights to our beloved 14 bolt full floater so we have to be nice to the less than desirable axle supplier.

The CUCV Blazers did not have 60’s in them….unless, some gearhead like us won a lot of CUCV junk (including trucks and chassis cabs) and built a nice Blazer.

[vtblazer]

Originally Posted by mothertrucker424

what gears are ya'll running and what size tires?

i have stock gears and 33's and its killling me when i let off throttle
i would like to see what ya'll run or what a better set-up would be i would like to run 35's also but not till i re gear
and what ya'll using for lockers?

The first question would be what is your intended purpose?
Daily driver, weekend warrior or full tilt wheelin?

Second question would be what do you expect from the ride?
How do you want the truck to react?
Do you care more about miles per gallon or acceleration?

Give us the full monte and we'll help ya out.

[mothertrucker424]

i have a daily driver and a weekend warrior i wanna be able to tow and since its my DD i wanna be able to have a nice take off from a stop i don't wanna be creepin up to speed but i don't wanna max out at 70 is this odd or am i being realistic

i have a late model 350, 33x12.5 tires and when i let off gas i can feel my tires slowing me down

[vtblazer]

Originally Posted by mothertrucker424

i have a daily driver and a weekend warrior i wanna be able to tow and since its my DD i wanna be able to have a nice take off from a stop i don't wanna be creepin up to speed but i don't wanna max out at 70 is this odd or am i being realistic

i have a late model 350, 33x12.5 tires and when i let off gas i can feel my tires slowing me down

It's not the tires slowing you down, it's the wind resistance. (seriously)
Our trucks are like bricks being pushed down the road.

For most all around purposes, I've liked 4:10's the best with 33's.
Good acceleration, good towing and pretty good off road.
(would be better off road if you had a 465 due to a granny first though)

3:73's work pretty well also and would give a better highway cruise yet still be fair in all the other application's.

IMHO, I'd lean towards the 3:73's given the choice for a driver.

All depends on how far your willing to 'tune' things in, meaning there's a ton of options out there you could go with.
Tire size/gearing/over drive tranny/over drive add ons...all the above.
It's all about time/money and what your hoping to end up with.

[Zoomad75]

Here's my experience with gearing on my Blazer. Note that I havent changed the gearing at all, just tire sizes.

Starting out, 3.73's and 31" tires. Accelerates quite well, but at 70 mph it the poor 350 was buzzing at 2800 rpm.

Next up, same gears but 33" tires to fill the opening better and larger stance. Now 70 mph tach's out a 2600 rpm, but off the line power dips a little. Not much, but you could feel it.

Now I'm running 35" tires with the same 3.73's. RPM's at 70 mph dropped another 100 rpm to 2500. Off the line acceleration is way down and climbing moutain passes on the highway is seriously affected. Sometimes requiring running in second gear just to keep the engine pulling.

My 350 isn't the strongest out there, but I've realized keeping it tuned up helps. After doing plugs/cap/rotor and valve stem seals at Dirtylarrys place this weekend, I realize part of my hill pulling problem was the fact that I had a couple fouled out plugs. A couple of banzi runs in Larry's nieghborhood proved that little 350 still has some power left in it.

Point being, if you are staying with 33" tires, 3.73's is a good balance point. You still have decent off the line acceleration and not winding the engine like crazy at highway speeds. Bigger tires require more leverage to get rolling which is why you need lower gearing (higher numerically) to get them spinning because the larger tire travels further in one revolution than a smaller tire.

I can gain back the acceleration I had before with the 3.73's and 31" tires by running 4.10's with my 35" tires. Highway rpm at 70 would be 50 rpm less than it was with the 31's and 3.73's.

[special-K]

Originally Posted by mothertrucker424

what gears are ya'll running and what size tires?

i have stock gears and 33's and its killling me when i let off throttle
i would like to see what ya'll run or what a better set-up would be i would like to run 35's also but not till i re gear
and what ya'll using for lockers?

My first question is,"what gears do you have now?"Let`s establish a baseline.With deeper gears you`ll feel compression breaking more pronounced,but get going easier.With taller gears you`ll feel more of a "free rolling" effect,but feel "dogged" off the line.

[johnnywagon]

Heres my 2 cents: I'm running 36's with 4.10's and am very happy w/ this combo. This is not a daily driver but does see some highway action in the summer. My mildly built 350 gets about 8 MPG on the highway at about 60 MPH. As far as lockers go I've had great luck with my inexpensive Lock-rite in the 14 bolt. I've heard from other members that they work good in front Dana 60's but might be to weak for D44's. Plus theres the drivability issue with a front locker that is "always-on", so to speak. Virtually impossible to drive on the streets in the winter.

[1969k10stepside]

Well,that blazer had some 38s,or a size close to that.I know that it was a 8 lug.I think the guy probably did put a d60 front in it.

[mothertrucker424]

i think i have 3.55's does this seem right?
and i think its a toss up between 3.73 and 4.10? right?

i live in FL no 0 nada hills and i drive on highway once every month if that and i mostly drive in town and wheel on weekends in muddy conditions

i have 33's but plan to upgrade to 35's after regearing
my motor is fresh too so its really jumpy and ready to go

and when i say i can feel the tires slow me down its almost like i drop a gear but not that hard of a decel am i making sense or rambiling?

[Zoomad75]

I'd say pick a gear for the tire you plan on running. Like I said 33" tires with 3.73's is ok, but if you then jump to 35's after regearing you'll be back in the same boat. If you intend on using 35's for sure, go with 4.10's.

The feeling you have of the tires slowing you down sounds normal to me. These trucks don't coast all that well. The only time mine doesnt slow down when off the throttle is when I'm coming down a long hill or mountain pass.

[Americanrider]

[QUOTE=and when i say i can feel the tires slow me down its almost like i drop a gear but not that hard of a decel am i making sense or rambiling?[/QUOTE]

You might want to look at some other issues that could make your truck feel that way. Kinda' like she don't roll to easy on it's own. It could be any number of moving parts, like a bearing or gearset getting ready to self-destruct and causing rolling resistance. My 67 was doing that, it was a rear wheel bearing slowing me down, after I fixed it I could coast accross an entire level parking lot.

Here is what I would do:
Inspect All 4 wheel bearings & re-pack.
Inspect for dragging brakes, adjust.
Inspect & lube every u-joint on driveshafts.
Drain & refill diffs, check for metal shavings.
Drain & re-fill Tranny & transfer, check for metal shavings.
And last but not least, Check tire inflation.