1994 6.5L NA K1500; input please

[GM Guy]

Hey guys,

I have located a 1994 K1500 ECSB 6.5L auto 4x4, and I had some questions:

could one expect better fuel economy in empty and lightly loaded vs an identical turboed rig?

does this have the 4L80E or the 4L60E?

how is the performance of the NA 6.5L electronic engines? pretty comparable to my 91 6.2L?

would it have the SF 14 bolt, or the 10 bolt?

what kind of fuel economy could one expect with 3.42s?

of course you guys are wondering why the most pro-manual, anti-4wd guy wants an auto 4x4, and the answer is my boss is sick of the fuel economy he gets in his gas rigs, and needs a new run around. bed will be full of tools and supplies, and will rarely tow a trailer, and if it does, it will be small.

any input appreciated, thanks!

 

[GM Guy]

okay, I got some answers from the guy finally, he gave up the VIN and it does have the 4L60E, and the NA engine is the L49, so surely if it got the 4L60E, it probably has the 10 bolt surely?

He also said that he only got 13-14 mpg! :O I hope he never left town, or that something is wrong, because that surely isnt accurate, is it?

 

[ak diesel driver]

we have an 84 that when my dad first got it got around 22 on the hiway

 

[buddy]

The truck should do well over 14mpg. He must be mistaken or something is wrong with it, like a clogged air filter. you can get a reflash for the N/A just like you can for a turbo truck that would help mileage and power a little, and disable the EGR programming.

I have a 94 with 3.42s and it is 10 bolt. rolling on a flat highway at 75mph I can get 20mpg, and normally around town and to work (which is mostly 45mph with some stop and go) 17mpg, and I have a heavy foot. The NA trucks should have more efficient exhaust manifolds, but if it has the stock exhaust that should be the first thing upgraded. Then the EGR can be blocked and hog out the upper plenum at least, if not replaceing whole lower intake. On a NA I dont know if the air filter itself is a big deal because it doesnt compress all that air into the engine like the turbo, but at least for the turbo trucks the rectangular filter stinks.

 

[GM Guy]

so on a NA, is there a split intake, with a special upper to adapt to the round filter, with the same lower as a 6.5L turbo? or is it just the same as a 6.2, and one would need to get the same as the j-code 6.2L?

those kind of figures on MPG sound much more like it. so do you think that the NA has the opportunity for better mpg than the turbo, due to the free flowing intake and exhaust systems? (at least empty, loaded is another story)

 

[bk95td]

Get a "J" intake. I got around 22mpg with my 91 6.2. It should get at least that good because I had 3.70 gears and a heavy foot. I would be leary about a 4l60 trans. The 700r4 that i had was a pos . The 4l60[electronic 700r4] can be made stronger with a bunch of $$$$.
Injectors and timing chain could help the mpg.

 

[buddy]

I dont know what the stock intake on an NA 6.5 is, I assumed it was just like the turbo intake with the filter in the same place, just no turbo inbetween.

I am also leary of the 4L60E just because I have one in the Z28 and I broke it, and everyone I talked to that has had one has had to replace one. Although I think the issues have been addressed in any new or rebuilt ones. And I had a 700r4 in my older camaro, tore it up once and that was just with a V6. Although, many people have them going many miles.

He could always change it out for a 4L80E if he ever had an issue, just make sure the wiring harness is correct, the PCM is the same just a different EPROM needed.

I wouldnt mind having an NA one for the girlfriend to drive.