turbo master is not the answer, it is a part of a set (turbo master to kill vacuum system and chip to make the computer accept that/add fuel for the extra air). Sorry you got fucked that sounds terriable. My dually 3500 has 4.10's and is running ~3000 at 75 mph i get that they are low on air at these rpms but with the stock turbo, exhaust, chip, turbo master it runs pretty good. there is always better, but if someone says they dont want to go crazy the simple bolts ons tend to be a sufficient answer. I drive allot of these trucks un-chipped running 4-5 psi and i can tell you my junk is leaps and bounds ahead of stock. could it use a bigger turbo? yup.

 

The TM set at 8 psi should work on stock tuning.

On my 94 K3500 I run an a team turbo and stock tune, performs great. One day I'll tune it also but for now it does everything I need but has alot of more pressing issues.

 

hmm my C3500, 4l80E, w/ 4:10 ratio, G80 axle, w/ 235s @ 75mph is 2500 rpms on the dot.

At 3000rpms, Im pushing triple digits.



One good thing came of my pain.. My wife begged me to take over the wrenching and I can now hotrod the s'it out of her, do WTFE I want so long as it never graces another stealership service bay. Got wifes blessing

Now if I can just find a '50s panel truck or rat rod project for the right cheap price to transplant my engine and driveline in..

 

I'll have to say I agree, 3k at 75 is a bit high. Are you sure you have the correct alt pulley? Parts store alts have a smaller pulley than OEM 6.5's had.

Mine is bout 26-2700 ish iirc but I rarely have a need or road to go that fast on. That's also on a NV4500 with a lower geared OD than the 4l80

Now my truck with 4.56's is another story on rpms .

 

its possiable the gearing has been changed or it has a replacement glove box in it but the rpo code says it should be 4.10, to be fair i have never checked physically checked it. Im not sure i have enough rpm to get into the triple digits and if i do it'll be beyond red line. I'll snap a pic later and im almost 100% its not a alternator pulley issue. This engine, computer, exhaust, accesseries, everything just came out of a 2500 suburban and it was all right on and it ran lower cruising rpm which is more in line with what you guys are saying. man this thread has gone off the rails.

 

I have a 1994 k2500 6.5 NA which I just bought and needed a starter, I know that these motors arnt that desired in the diesel truck world but I got a really good deal on it. I even have a brother with a 99 24 valve and he even said it was an alright deal. It takes a lot for him to say that being if its not mopar or Cummins he hates it. But I was wondering which years of these were mechanical or electronic?

 

https://en.wikipedia.org/wiki/Detroit_Diesel_V8_engine

 

Being non turbo it has a chance of being a Mechanical but by only knowing the year I'd say DS4.

It should be easy to swap a turbo in it but you need to check if you have a 4l60 or 4l80