Highway Screamer!

[UltraBlue71]

I am 6 months into my build and finally cresting the hill on the downward slide, finally started some painting last night!
Its a 3/4t with a dana 60 reaend, and the saginaw 4spd top loader shes geared so low I just use 3rd and 4th, I can start out from stoplights in 3rd!Friends riding with me think its hilarous that I have a 2 speed (Low and high). So needless to say it screams at 65-70 mph 3200rpm, My question is should i get a new rearend or swap trannys or both, I dont really want an auto, I think a 5 speed would be cool, and I read a few of the S-10 tranny swap threads, but I just dont know if they will hold up. I eventually want to rebuild my stock 350 crate motor to 350-400 HP, any suggestions???

[texanidiot25]

What size tires? I moved up to a 31" x 10.5 truck tire and that helped out my highway cruising quite a bit. Other than that, with our D60s, it's the slow lane for us

[spinning wheels]

You might try getting a manual trans out of a newer full size GM truck. Or look into a V8 GM car with a stick shift, mainly the F bodies Camaros and Firebirds.

The S series truck's manual trans, might be a bit weak for a V8, especially if you plan on upgrading the stock 350.

That's if you don't want to switch to an automatic trans.

My 3/4 ton also screams at approx 70 mph. I say approx, cause the speedo bounces all over the place. That and with flowmaster 40 dumping just before the rear axle, all I hear is the exhaust. I am running Bridgestone Desert Dualers, 31" tall tires in an attempt to lower the rpms. The truck has a turbo 350 in it, at this time.

[Longhorn Man]

if you actually have a dana 60, then just get a gear swap in there.
If you have the eaton (much more common) then you are stuck with a tranny upgrade, or rear end swap
Your cruise RPM makes me think you have a 4.10 gear... takin off in 3rd os a little rough on your clutch and the heat will damage your flywheel.

[Indyuke]

NV4500 and 3.73 rear. Nice combo

[special-K]

What`s wrong with running 3,200rpm.That`s what we all did before o/d.I cruised my 4.10 equipped`71 Camper truck all over the country @ 70-80 mph.It seemed happy to me.Still have the original never rebuilt motor.Lower rpms is a good thing.But how much will it cost?You won`t hurt the truck running as it is.Most people are just used to o/d these days.

[69halfton]

special K has a very good point.

by the time you have made the swap, how much money have you spent?

how many years will it take to make that money back in gas SAVINGS?

just think...3200 rpm...its right in its powerband

[texanidiot25]

Fuel mileage is one issue.

[UltraBlue71]

You have a point Special-K, I have a 2002 Tahoe, and my wife drives a Hundai Sonota (yeah i know...) When you are used to these overdrives 3200-3500 at 65-7O Mph just seems like I'm running the heck out of the motor, turning lower rpms might gain me a few mpg's if I'm lucky, a gear set for my Dana 60 is under 200 and that might be what I'll try first, so a 3.73 would be the way to go then?

[grayw0lf]

Thats nothing! I have a '70 C-10 w/ 4.56 out back. I stepped up from 27" to 31" tires & it has helped a bit, but still way too low!

[jfaithbass]

My '71 C-20 is the same... eaton rear with the 4.11..... and its about to get swapped for a new frame with the leaf spring rear and a dana and 3.54 gears... i'm hoping to see a diffrence in cruise and still have enough bottom...

you should drive my 1930 AA ford.....the engine won't make it to 3000 rpm and its got a 6.60 rear axle ratio.... top speed 35

jeff

[special-K]

I drove my CustomCamper/20 with 4.11s from Maryland to Taos,Durango,4 corners,North Rim,Sedona,and back and never gave it a though except when I was enjoying hearing that sweet pitch coming throgh the jalousy windows..
These Dana60 trucks were available with 3.54s...better yet over 3.73s.My`72 has them and it runs great all around.It catches second with 12.50/33s and still rolls down the hiway nicely.

[pmpski_1]

I've got the Dana60 with 4.10s and have decided to keep it that way with my TH350. Some good points here - how many miles do you have to drive to get the cost back, etc.

I'm used to driving at a lower RPM so I thought I was killing it at 65, but I guess I'm not.

One more thing - UltraBlue71 - M I Z....

[UltraBlue71]

-ZOU...GO TIGERS! BIG 12 ROX!


I just want her to last another 38 years (or more) for me to enjoy with my kids and grandkids. Shes just gonna be garage furniture for the most part.
The rudementary nature of the beast is part of the fun I suppose, low gears, 4spd, loud exhaust, windows down, vent windows swung open, floor vents open, me and my 3 boys ( all double buckled of course) headed out fishing or for an icecream cone.
My old man loves these year trucks he always had one done or inwork when my brother and I went to visit him during summer break, back when we were little. Late (80's),
I guess I really just want my kids to apperciate this old iron as much as I do, American craftsmanship, the last of the all steel Chevys!

[LMN8UR]

This past weekend I installed a NP 833 into mine. I Love it, Why didn't GM sell more of these? I have a 2.7? rear and with the OD I'm turning about 1400 rpm at 65. Can't wait to run the first full tank to check the gas mileage, I've hit 18 highway before, is 20 possible in a flying brick?

[Longhorn Man]

at 1400 RPM, your MPG will probably drop.

[UltraBlue71]

LMN8ur what did that Np833 tranny come out of? Isnt that a 4 speed too? Are you running a gear vendors unit?

[hereinmissoula]

4.56's here from factory.... even with 33's it's ridiculous on the highway....

feel your pain...

then again i am kinda hard on things, and if something breaks it gives me good reason to replace it with something.. "better"