Can you cruise at 80+mph in your truck?

[Tito19]

Not a chance. 305,sm465, np205, 4.56, pushing 35"BFG's. @50mph she's screening.

[RIDE-RED 350r]

Originally Posted by Tito19

Not a chance. 305,sm465, np205, 4.56, pushing 35"BFG's. @50mph she's screening.

I'd say so!! LOL! I'm guessing about 2600 at 50??

[jeffahart]

Right now I'm running 33s with 4.56 sm465 and 350. Since there is no tach not sure of rpm but the whole engine, drive train and suspension smooths out around 63 mph. And it just rides nice at that speed, very curious indeed. I may consider driving it to the Brothers show and shine this year. But I have no real desire to do a long range trips in this truck or commute. I like to drive my car, it has become a great place to make phone calls. But I still enjoy Mall Crawling!! I love that saying!

One thing for sure; with this drive train you are forced into throttle discipline!

[Tito19]

Originally Posted by RIDE-RED 350r

I'd say so!! LOL! I'm guessing about 2600 at 50??

She runs around 2900 @50. But now that I think of it, the speedo is off due to the 35's. So that means the actual speed is above 50mph?

Also agree with Woodwright. The what happens between point A and point B is 100x better in my 69 truck then in a new car. Most the time.

[RIDE-RED 350r]

Originally Posted by Tito19

She runs around 2900 @50. But now that I think of it, the speedo is off due to the 35's. So that means the actual speed is above 50mph?

Also agree with Woodwright. The what happens between point A and point B is 100x better in my 69 truck then in a new car. Most the time.

Easy to check...

If you have a smartphone, get yourself a free GPS speed app and check your speedo error...

[woodwright]

There's kindof a theme in this thread. It's how I feel too. With new vehicles, I just wanna get there. In my old rides the journey is half the fun. And driving a nice old classic on the freeway, most of the traffic slows down to take a look.

[wilkin250r]

I used to routinely drive my 1972 at speeds of 70+ for a couple hundred miles, but it was also 2wd, so I think it had a little better road manners. No front axle means no death wobble.

[63burb]

My 84 k10 on 35's will do 80 all day and all night no problem...... If I'm going down hill lol up hill I'm doing 55 or less. I love my truck too much to abuse it like that, unless I have a LS swap 5.7 or maybe 6.0 or 6.6 lol with upgrade diff transfer then I would do 75 the most.. Tickets out here in California are not joke..

[Matt Man]

This is why I like my 3.08 gears with 33's...sometimes the power around town sucks, but on the highway she cruises nice at 65mph and 2350rpm.

[72chevyk10]

4.56 and 35's is about 2600 at 60. and what i usually top out at. had it much higher before though and it did fine

[Tas0718]

I have drove my 87 burban 75 mph from central Louisiana to New Mexico and back a couple of time all interstate and it did great. I have a 350tbi with 700r and 3:42 gear with 35" tire.

[RIDE-RED 350r]

Originally Posted by Tas0718

I have drove my 87 burban 75 mph from central Louisiana to New Mexico and back a couple of time all interstate and it did great. I have a 350tbi with 700r and 3:42 gear with 35" tire.

I'm guessing about 1600 at 60mph??

[1976gmc20]

I used to have a 1980 K-10 that I bought new (traded in a 1973 K-20 for it).

It had a 350, four speed, and NP205. It was geared really fast from the factory so you really couldn't even use high gear in town. The tires were whatever came from the factory: highway tread P radials.

Legal limit was 55 back then but down in Northern NM where I was working there were no patrols. So as soon as I crossed out of Colorado I would open her up to 80+ mph and she just purred like a kitten and still got 15 mpg, Handling was rock solid, but of course it was brand new at the time.

So yeah, 80mph is no problem given the right gearing and the steering and suspension are in good shape.

[dieseldawg142]

yeah, i drive my k30 crew at 80 on the highway all the time- 80 KPH!
80 k's is about 50 mph, but with the 39" tires, i'm actually doing 56-58 mph- which is about as fast as the big block likes with 4:56's & a T400 (just under 3 grand on the tach)

[Ranger6202]

I drive my '85 crew cab @ 75-80 mph on the interstate all the time.
LS Lq4 6.0 - TH400 - NP205 - 4.10's - GM 14bolt/Dana44HD on BF 35's. Tach reads about 3k-3.3k
As soon as hunting season is over i'll be swapping out the th400 with the custom 1st/2nd gear (2.96 1st) 4l80 I just finished building to get them RPM's down.

[webfoot]

My 71 K-20 (sold over a year ago) was a great cruiser at any speed and it was my daily driver. That was after new steering linkage, box, rag joint, shocks, and tires. The guy I sold it to drove it from here to seattle then back down the coast to LA where he lived.

I don't know about 80 but I drove it at 75 pretty regularly. Sure, it was up there in RPMs (maybe 3-3500) a bit but this is a SBC we're talking about, not a diesel.

[74CustomK20]

My k20 in my signature does great on the highway, mud, and anywhere really. I've driven it on the interstate, twice, and it did alright. Stayed around 70ish and just floated along. Now? Hell I'm only 22 but don't get in a hurry even lol. I purposely take the highways and back roads in her to enjoy the scenery with the doors off... good memories and times with the little one and old lady!