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Discussion Starter #1
Hello,

We just bought a '98 K1500 Suburban with ~87K miles. Looks like a nice little forum here, wondering if you folks could answer a few questions.

1) What kind of engine is the 5.7L Vortec? OHV or OHC? SEFI or other? timing chain or belt? Would you classify it as mass air or speed density? anything else to know?
2) Since this is my first OBD-2 vehicle, the wife offered to get me a scanner for Father's day + birthday +.... Any suggestions on a good DIY scanner that will provide reasonable access to trouble codes (including GM specific codes, if possible) and PID's. Don't want to break the bank with this one either. Not too worried if it's backwards compatible with my Ford EEC-IV vehicles either. I can pull trouble codes on them with nothing more than a paper clip and I don't think either of them will output PID's to a scanner
3) I guess the transmission is a 4L60E, is that right? Is it a good transmission? What kind of gear ratios? Does it need any special attention other than periodic fluid changes/filter changes?
4) What about the transfer case? What shall I call it (I have 2H, 4auto, 4H, and 4L options)? What's the low range ratio on it? What's the basic operating principle behind the 4auto setting?
5) While discussing the 4x4, what's the mechanism for the front axle disconnect? Is it reasonably reliable? How would this be disabled to acheive a 2L setting (for backing up trailers and such)?
6) How do I determine what my differential gear ratio is? What are the chances I've got a limited slip differential and how would I find out?

I'm sure there will be other things come up, especially as problems surface. Thanks in advance for any information.
 
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Hey, getting ready for work and just wanted to say welcome to the site. Hopefully one of the guys will log on and can answer some of the questions for you.
 
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Well, those certainly are some specific questions. I wish I could provide the answers you're looking for. However if nothing else a forum is a great resource for ways to get the information.
I would like to refer you to a previous thread about restoration packets from GM.

While you might read that I was a bit dismayed by what I received from GM, I have to admit that as long as you can identify specifics about your vehicle, you can piece enough information together from the packet to be able to figure out what the exact details of your 'burban are.

Give GM a call, they will ask for your VIN, so have it handy. I received my packet in about 2 weeks.
Considering the price (free, if you live in the US) it's worth it.
 

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Discussion Starter #4
I'll have to try and see if GM will send me one of those packets.
Been trying to find answers to these questions, here's what I've got so far:

1) The manuals call engine managemet a "central sequential fuel injection (CSFI)" system. I understand (basically) SFI, but what's with the "central" designation?

4) Haynes said there is a tag on the t-case that identifies it, so I got underneath and the transfer case calls itself a "New Process 246" and claims to have a 2.72:1 low range.
 

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"Central" is probably marketing/promotional jargon. :)

What do you plan on doing with those gears?
 

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Discussion Starter #6
I don't know that I'll doing anything real special with low range (I also recognize that a lot of people never have any use for low range). Mostly off road cases where speeds are slow and the gear reduction will reduce strain on the engine/transmission. If I figure out how to disable the front axle disconnect, I find it useful for backing trailers.

3) I've also found some information about the 4L60E/4L60/700R4. http://www.maliburacing.com/auto_tranny_id.htm note that the 4L60/4L60E are descended from the 700R4. It's got a fairly wide spread in gear ratios (some called it the widest spread out there). That can be good or bad, depending on your take.
I also found that GM sells the 4L60E and a controller so you could put it in older, non-computer controlled applications.
new question: does anyone know if the computer will lock the torque converter clutch in 3rd gear (if I'm in D instead of OD) as well as 4th gear?
 

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BTW, 87K for a 1998 is pretty good for miles.

I don't know if they used computer controlled torque management in 1998 or not. I think that they would.
 

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Discussion Starter #8
Still learning new things:

6) Rear end is a GT4 (3.73) with a G80 locker. The G80 is a kind of locker made for GM by Eaton. It is normally open. At slow speeds (below 20 mph), if one wheel slips, it has a mechanism inside that will lock the rear wheels together and put power to the wheel with traction. It seems to work ok. With the roads partially plowed, I put one wheel in the snow and one wheel on the dry pavement, and it did grab. We'll have to see how effective and reliable it is.
 

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Anything you would like to find out more about just open the glove box. Inside you will find the build lable with all the equipment the truck was built at the factory with. They are just a bunch of numbers and letters but you can decode them farely esily.I used to know most of them but all these newer trucks I am really not sure of the codes.
I am sure that the trany is electronicly managed tho. I have a buddy that does all my trny work and he wont touch these newer ones with all the electronic controlers in them, says its cheeper an easier to just order a goodwrench and drop it in.
 
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Yeah, that's the way that just about everything is going these days. Order a new one and core the old one. Ends up being cheaper on the labor. This goes for lawn mowers, computers, etc.
 

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scantool.net has a great little interface for the ODB 2 stuff that you can plug into a computer via a serial port, then you can use their software or several other free applications like digimoto. They have different functions between the apps. The ScanTool one is pretty effective from my experience but the DigiMoto one has a better User Interface.
 

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MrShorty said:
1) What kind of engine is the 5.7L Vortec? OHV or OHC? Timing chain or belt?
2) Since this is my first OBD-2 vehicle, the wife offered to get me a scanner for Father's day + birthday +.... Any suggestions on a good DIY scanner that will provide reasonable access to trouble codes (including GM specific codes, if possible) and PID's. Don't want to break the bank with this one either. Not too worried if it's backwards compatible with my Ford EEC-IV vehicles either. I can pull trouble codes on them with nothing more than a paper clip and I don't think either of them will output PID's to a scanner
3) I guess the transmission is a 4L60E, is that right? Is it a good transmission? What kind of gear ratios? Does it need any special attention other than periodic fluid changes/filter changes?
MrShorty said:
new question: does anyone know if the computer will lock the torque converter clutch in 3rd gear (if I'm in D instead of OD) as well as 4th gear?
The 5.7 liter Vortec is the good old tried and true Chevy small block v8. Push rods, cam in block, overhead valves. The Vortecs are vastly better engines than the older throttle body engines, and the heads actually flow pretty well for decent performance. This engine is basically an evolution of the original small block released in the '50s, and does have a timing chain.

As far as the scanner goes, if you only wanna pull codes, Advance Auto Parts, Auto Zone, O'Reilly, Napa... You name your local parts store, should carry what you're looking for. Just make sure that you can erase the codes that it pulls. Not that you should ever need to, but just in case. I definately wouldn't spend more than about $50-$60 on one of these.

The torque converter as far as I know, will not lock up in third (D) gear. You're at 87k miles, If the truck wasn't used to pull regularly, and didn't spend extended amounts of time where the ambient air temp was 90* plus, you can probably wait until around 100k for a trans service. By the sound of it, you're gonna pull, so change that fluid every 15k or so, and alternate every other service with a trans flush (more expensive, but also more thorough), not just the drain and fill method. Invest in a trans cooler if you don't already have one!

As far as the G80 diff goes, they do seem to be pretty reliable as long as you don't abuse them. If you start building power and relish making big smokey burnouts and donuts (who doesn't!!), you'll wanna upgrade.
 

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Discussion Starter #14
Been a while since I checked this, but thanks for the additional replies.

Scanner discussion: I'm definitely looking for something that will do more than pull/clear trouble codes. The Elmscan5 available at scantool.net seems interesting, any experience with it? It seems that its abilities are tied mostly into what software you choose to run. I've also been considering something like the Actron CP9145.
 

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the elm scan from scantool is what I have, I have had some fun with it but haven't had time to really put it through its paces. I have used it with the scantool software and the "limited" freebie digimoto software. You can get a good look at both of them by just downloading the software and running it without even having the scanner. Digimoto is the "nicer" interface but since its a pay to unlock all the features I ususally use Scantool. They both support windows / Dos environments as far as I know not Linux or that other fruity software. ;-)
 

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Hello,

We just bought a '98 K1500 Suburban with ~87K miles. Looks like a nice little forum here, wondering if you folks could answer a few questions.

1) What kind of engine is the 5.7L Vortec? OHV or OHC? SEFI or other? timing chain or belt? Would you classify it as mass air or speed density? anything else to know?
2) Since this is my first OBD-2 vehicle, the wife offered to get me a scanner for Father's day + birthday +.... Any suggestions on a good DIY scanner that will provide reasonable access to trouble codes (including GM specific codes, if possible) and PID's. Don't want to break the bank with this one either. Not too worried if it's backwards compatible with my Ford EEC-IV vehicles either. I can pull trouble codes on them with nothing more than a paper clip and I don't think either of them will output PID's to a scanner
3) I guess the transmission is a 4L60E, is that right? Is it a good transmission? What kind of gear ratios? Does it need any special attention other than periodic fluid changes/filter changes?
4) What about the transfer case? What shall I call it (I have 2H, 4auto, 4H, and 4L options)? What's the low range ratio on it? What's the basic operating principle behind the 4auto setting?
5) While discussing the 4x4, what's the mechanism for the front axle disconnect? Is it reasonably reliable? How would this be disabled to acheive a 2L setting (for backing up trailers and such)?
6) How do I determine what my differential gear ratio is? What are the chances I've got a limited slip differential and how would I find out?

I'm sure there will be other things come up, especially as problems surface. Thanks in advance for any information.
Hard to believe this thread was started back almost 9 years ago!
 
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