Do you keep it under 2000 when possible just to avoid an over-rev situation? Would like to know why you try to shift before 2K so I can adopt same practice... Is that the max torque range by then? Do you run a boost guage?

Thank you for the break down of your shift points. I have not been paying that much attention to the actuial speed as much as engine noise and the tach readout - so I'll pay attention next time I get the truck out. It is getting a few days rest while I dirve my other car some. Try to rotate to keep the batteries fresh etc...

I have found that I need to start in first on hills and can easily start in second when, if ever, I roll a stop sign or have a merge lane etc...

As for my son he is doing much better - I hate to feel the truck stall or buck and hop but he is almost past that stage now and the truck and the tranny/clutch seem to have held up fine. Many friends have asked me what I am thinking teaching him on that size of a truck - well that is all I have to teash him on! I learned on a Honda XR80 dirt bike then a 82 Mazda 4 cyl sedan 5 speed. Drove quite a few Datsun straight shifts when they still called them Datsuns.

As for catching the red lights - I know what you mean. I keep an eye on them but I am convinced that when I drive downtown in my car I get green for miles and in the truck it turns red every block Gives me time now to pay attention to the mph and to keep it under 2K RPM huh?

~GOD BLESS~

john

 

Well, I keep it under 2000 rpm to get better mileage and its easier on the engine. I wish these had 6 speeds so I could keep it between the 14-1900 rpm range but keeping it under 2000 rpm is how I was taught really to shift low and keep the rpms a little low. I think you hit max torque at 1800 or so, but when the engine is down at 11-1200 rpm it might be harder, I think after you shift if you hit 14-1500 you're prime, but I keep the rpm low and I'm not hard on the acceleration so the little power you get then doesn't bother me. I'd only do it depending on your driving habits, I'm slow and take time to get up to speed, I get a lot of hand signals too, so at my pace I don't draw smoke at all, but you can really lay the coal if you lug it down that much and try hard acceleration. This is only for slow acceleration, faster you can probably add 10 mph to each of the shift points. I also do it this way so when I shift up, I don't end up slowing down much from the transmission, I looked in the owner's manual and they said 2nd to 3rd at 25 and that's around 2500+ rpm! and when you shift to third your front end bobs down and you end up slowing down. My shift points keep me from playing the clutch much so my clutch should last longer too, I fully disengage the clutch after a shift to start accelerating again.

I don't have a boost gauge. Planning on getting one though. But when you go down the that low of rpm, boost is little to none.

Well, I started on a Suzuki DRZ-125L, then went to the Isuzu for highway use. Since then I upgraded to a Honda XR650R, and whew, you want to talk about some giddy-up, that thing will lift the front wheel off the ground with pure throttle.
Now only to get my 6.5 that type of power.

As for teaching to drive a manual, I think its better on a larger truck, since its harder to kill them. I learned the key is to just find the sweet spot on the clutch and it makes a world of difference when learning.

I do use first when starting on steeper hills, but I've been doing 2nd gear starts recently, seems when I want to shift from 1st to 2nd someones about to run into me.

 

OK. That make sense about keeping the RPMs down. I have noticed driving the 3500 versus the Burb' a loss in get up and go - but that does not bother me as I also am not driving for speed (with the occasional interstate run not included)
I just want to get myself and the truck safely to the next stop. I am interested in the boost guage with the NV4500 to see how it compares to the boost I made with the Burb' and its automatic. I rarely made over 5-7 PSI in the Burb before it would shift under regular driving conditions. Under heavy throttle it would kick out (wastegate) at about 13 PSI. But the Burb had a cold air intake and a 4" straight back exhaust. My New to me GMC has all stock exhaust and air intake so I'd expect a little less boost.

Cool to hear about the dirt bikes - you are right if we could do the add ons to the 6.5 that you can do to a bike to get more power we would all be blown away!

But I also like not getting caught up in the power adder game - I admit I was into it too hard when I had the 7.3 Powerstroke. Always seemed like something was coming next. That hurt the wallet.

I am going to take the truck out for a good drive this weekend on some back roads and to let Ben practice some more. I'll have him watch and record the mph and RPM when I shift so I can report back what is happening. I'll try a few hill starts in 2nd to see if it pulls - makes me wonder what gear is under there. I asked the guy I traded from and he said he did not know. Is there a tag on thge rear end with the gear on it?

~GOD BLESS~

john

 

Klein look in the glove box there is a sticker there or should be with a bunch of codes GT5 GT8 or maybe a GU# these are axle codes more than likely being a 1 ton you should have a 4.10 gear under that truck

 

Thank you Mayhem - I'll check the glovebox if not tonight (have to do my taxes) then this weekend and post the code here to find out what the rear end is. My ford has a metal tag on the rear diff that tells you.

I appreciate your input on where to look and what is most likely under there now.

I don't want to sound like the truck is a slug - it gets up and moves. So I don;t think I have too low of a gear back there.

~GOD BLESS~

john

 

Well, at 55 mpg I'm runnin 1750 rpm with 3.73 in high, I think the 4.10 run about 2500 rpm at 55. Those are the two most likely gears ya have.

 

I ran the VIN as suggested in this thread:
https://www.dieselbombers.com/chevy-...-5l-turbo.html

And it says the truck has 4.10 posi rear.

I know that at 70 mph it runs about 2200 - 2250 rpm in 5th.

~GOD BLESS~

john

 

That's what I'm running, I bet you do have the 3.73s, I got them and run that. I know I was talking to Racer55 and he said his runs 65 at 2700 and he knows his stuff, he has the 4.10s. As for the posi, I doubt that you have one. It should be limited slip by 96, mine is limited slip, posi ones aren't good when cornering and wouldn't have lasted this long.

 

A G80 code in the glove box would indicate a heavyduty positive traction rear end in theses trucks

 

They still put posi-trac rear ends in this late? I thought by then they would have put limited slip in everything.