GMTDScanTech vs Tech2

[gmctd]

Affirmation - Swedeburb's excellent OBD1 pcware scantool is excellent.

Every point compares exactly to data scanned with the Vetronics Tech2.

However - there's that inevitable 'however' clause, again - it is much more versatile in specific function than the Tech2.

The '08 release of the OBD2 enhancement will make it the kick-assimilating pcware scanner for the GM 6.5 EFI systems.

I would recommend GMTDScanTech, and it's freeware basic companion, GMTDScanBasic, to anyone wanting or needing to know more about their ride.

gmctd, aka jd

[gvig]

Are you saying there will be an OBDII version? On Jan. 23 Stefan said he could not justify the time, do you know something he is not yet saying?

I just gave up on my 95 and bought a 96 which moves me into OBDII territory, and I hold key number 12 for GMTCScan Tech, never got to use it :(

Tech seems the way to go, a OBDII version would really be super:)

George

[gmctd]

No, my bad, George - the OBD2\CAN licensing fees will likely prevent an OBD2 upgrade.

I was hoping for an upgrade also, as GMTDscanTech is more versatile than the Tech2, imo

BTW, what happened to your '95?

[gvig]

A sad story, the engine had developed a voracious appetite for antifreeze. Nothing was showing in the oil so it was all going through the cylinders. I pulled the engine in December but due to previous time commitments (church building trip to Ecuador) and ongoing family issues (ill relatives) I was unable to disassemble it till this week. Upon tear down I discovered the heads were cracked so badly I wondered how it could have been running so sweet.

I pull a fifth wheel, weighs about 9K when we hit the road. The block is a 506 cast on April 27, 99, one of the weak ones but no cracks. The only way I could justify building it would be to go with splayed mains and lowered compression, make it work and make it last. With new heads, pistons, boring, machine work, new main caps and all, I added the cost to put it back on the road and the price came to more than the truck would have been worth.

Hard decision.

The truck has 446,000 on it and has served me well for the time I have had it and what I have asked of it. NO complaints here. It still looks good, really good, I have replaced all suspension bushings, rebuilt the front end, rebuilt the transmission, and added some small goodies (check the sig) but there came a point where the romanticism of driving a truly high mile truck in such good condition was outweighed by the stark reality of economics.

Found a 96 1 ton crew cab dually with only 145,000 miles on e-Bay, bought it for $8,500, now I just have to figure how to get to Cody, Wyoming to drive it home. Airfare without advance purchase is crazy, so it looks like a long bus ride for me.

George

[gmctd]

Wow - 500kmi, one MrGoodwrench engine - what was the DS4\PMD history?

[gvig]

Note, the truck is a 95 but the engine I pulled and tore down was a Goodwrench replacement that had been installed at about 170K. I am the second owner. I had known the engine had seen some repairs but did not know until now that the whole thing had been replaced.

The truck has been through several IPs and an unknown quantity of PMDs. I bought it with 391K on the clock. In my care the PMD was replaced once, the IP once. The IP was replaced with a pull off replacement purchased off eBay, checked out by Thompson Diesel in OKC on a Stanadyne test bench/computer first, cheap fix and effective.

After I read, right here on TDP about the mounting screws coming loose on the transistors in the PMD, I started checking them, tightening as needed, never replaced one since, reused one I had previously condemned.

One thing I can't figure out is the turbo, it is not a late model (I can tell by the wastegate) but I have seen up to 24 pounds on the boost gauge. Of course I pull my foot when that happens, quickly. Didn't think the early turbos were capable of that.

George

[john8662]

Not Scantool Related...

Engine repower, sounds like that engine needs a set of Chinese heads like Robyn did and gaskets and assembled again and thrown back in the truck and driven just like you did before.

Maybe a stud girdle for the bottom end if you plan on keeping this truck as a spare for when you get to work on the '96 ;)

But, 24psi boost, yeah the GM4 turbo will do it, but it ain't efficient boost... For the sake of gaskets and heads, 12psi.


Scantool Related...

The GMCTDScan software makes it incredibly EASY to manipulate the features we need to manipulate on the 6.5, I can't say that for the Tech2.

I just need a longer USB cable since I don't have a Portable PC, just a PC sitting on the top of my Red Toolbox.

J

[derekja]

Are you saying there will be an OBDII version? On Jan. 23 Stefan said he could not justify the time, do you know something he is not yet saying?

I just gave up on my 95 and bought a 96 which moves me into OBDII territory, and I hold key number 12 for GMTCScan Tech, never got to use it :(

Tech seems the way to go, a OBDII version would really be super:)

George

I just hooked up carcode (http://www.obd-2.com/) to my 1998 K3500 for the first time today. I've got a bunch of engine work to do, so I couldn't play with the running gauges and graphs and such right now, but it does enhanced codes pretty well and seems like it has a bunch of buried functionality. Usability is more questionable, but hey I've messed with it for all of an hour now, so I've no doubt it will get easier to figure out as time goes on. Price is good. I picked it up for under a $100 on an ebay auction from the maker on a cable that had been returned and fixed.

Once I get my engine work done and can play with the rest of it I'll post a more thorough review...

[gvig]

John,

Non scan tool related: I thought about the quick fix, just didn't seem right to me. I have never built the cheap way, prefer to do quality work and make it "right." Clearwater heads don't scare me.

I know the GM-4 isn't efficient at high boost, only saw the big numbers on two occasions, not a regular thing.

Scan tool related: What pc based OBDII solutions are available that approximate the ease of use the Tech offers for OBDI?

With the Key on/key off deal on OBDII does one really need a Tech 2 ability or just the ability to read accurately the TDCO to determine what was set?

George

[gmctd]

We know the stock engine makes enough btu to pump that much Boost, but we just don't do it, for the reasons you're discovering.

You must do a scan to determine the as-is timing reference before you do the ko-ko routine - the scanner should eliminate the need for the manual routine.

I think Kennedy Diesel has something in the back room, but don't know how it compares to Tech2 or any of the other OBD2 pcware

[john8662]

Back when I had my '96 Tahoe I had to mess with timing, I searched for OBD-II software at the time and was somewhat disouraged by the price and the licensing (autotap = 1 year use).

The closest I came to buying an OBD-II package was carcode.com's stuff.

I didn't do it, Just paid a mechanic to use his scan tool to see the value, moved the pump and did the K/O K/O method, problem solved, it was in range as opposed to being off.

I'll stick to OBD-I stuff...

J

[gvig]

I think I know when the monumental cracks started in my heads. I was on vacation two years ago, got caught on a climbing, twisty, narrow road, through the wheat fields of southeastern Washington in late summer, hot as blazes. No where to get off the road safely, no shoulders. Engine started to overheat, then went ballistic. Hadn't yet done the cooling upgrades. It got so hot I was sure it wouldn't restart when it cooled off. Heard some scary "crack" sounds periodically while it was cooling. It restarted but started drinking and just got progressively worse.:(

The sad part is I had just that morning, before starting out, checked the water in the overflow tank, accidentally left the cap loose, my bad, my very bad, I caused it myself :mad:

Boost is normally limited to just over 10 pounds. A couple of times I really stuck my foot in it with the wastegate stuck shut but not more than two or three times and then only momentarily. Already using water at that point. I'm crazy, but not that crazy.

The OBDII world would benefit from Stefan making a stab at an upgrade. He has a good handle on user interface design and functionality.