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Saturday, August 27, 2005

The GM - Isuzu Cabovers; Pt.1

Chevrolet Tiltmaster
It never fails to stand that the quickest, most affordable way to add new product is to simply badge-engineer. And while GM has resorted to such many times throughout its history, it's rebadged Isuzu tiltcabs of the 1980s helped fill an important gap in the GM Truck lineup.

With the ink just dry on the international agreement, GM began implementing it's 'strategic alliance' with Isuzu in 1971. Unlike the recent fiasco regarding Fiat S.p.A., this purchase led to vehicles being developed and placed into production.
Bedford KB Pickup
The first fruit of this vehicular marriage arrived on U.S. shores in 1972 as the Chevy LUV, but other rebadged variants of the Isuzu KB Wasp/Rodeo pickup were sold under the Bedford nameplate as well. Global regions would again be covered with the T-Car, arguably the first true 'world car platform'.

Chevrolet Series 60 Steel Tilt
But perhaps the most important and influential product of the Isuzu GM alliance came by way of something larger: commercial trucks. GM was looking to replace it's aging medium-duty 72" BBC steel tilt, and minimalize design costs. Isuzu had just the solution: it's range of cabover trucks; Classes 4-8.


GMC Forward
Isuzu was looking to broaden it's production horizons, and GM offered them an outlet for that. Earlier in the 1970s, Isuzu trucks were sold in Australia under the Bedford nameplate, and their presence in South America and Africa soon became substantial.

Chevrolet Tiltmaster
It was then agreed that Isuzu's medium duty cabover trucks would enter the North American market in 1984. GM would market the Class 7 JCR truck as a Tiltmaster and Forward for its Chevrolet and GMC marques, respectively.

Isuzu KS22
Isuzu KS22 Interior
And as for the Class 4 and 8 trucks? While the 8 would never cross the ocean, Isuzu was allowed to sell the Class 4 KS22 cabover in the United States under it's own name.

Forward W7 Chassis
The initial offerings were very limited. Unlike the range of models and GVWRs offered on the outgoing Steel Tilt, the new Isuzu was restricted to a W7 / Series 70 model, and only offered a 27,500 and 29,700 lb GVWR.

Isuzu 6BD1 Turbo Diesel
Powertrain was similarly restricted. A tilt of the cab revealed Isuzu’s GBD1-T 353 cu.in turbocharged inline six-cylinder diesel, which yielded 165 hp and produced 335 lb/ft torque at 1900 rpm. This was routed through one of two variants of a 5 speed transmission; one featring a short fourth gear ratio, and then to a single speed rear axle, or a 2-speed Eaton rear end on the 29,700 GVWR model.

Forward/Tiltmaster Interior
What the new Forwards and Tiltmasters lacked in configurations, they made up in refinement. Comparing these new imports to the prior Steel Tilt was comparing night to day. Where the Steel Tilt had small vinyl seating, the new Isuzu sat three, and even had cloth weave available. Gone were the bare steel interior panels from olden days; the Isuzu featured plastic trim panels on doors and kick panels, and even sported vinyl headliners and floor trim.

Forward/Tiltmaster Dashboard
Drivers were treated to not only standard power steering, but a tilt/telescoping steering column, and a full dashboard – not some shrinky-dink instrument cluster on a steel berm.

Tilt Cab
The trucks were also a godsend to those who were responsible for their maintenance. Resevoirs, including those for brake fluid, windshield wiper solvent, and others, were accessible through doors in the dashboard. The oil level could be checked without tilting the cab, via a removable panel on the floorboards. And, should the cab need to be tilted, a remote-start provision was mounted on the chassis for quick testing.


GMC Forward
So how did it all work? Reasonably well. GM anticipated selling only a 1000 units in its first year. But with a total of 1300 GMC Forwards and 300 Chevrolet Tiltmasters in 1984, it worked better than expected. So popular were these trucks that total sales for GMC medium trucks rose 53%.

But this was only the beginning. And much change would come in 1986.

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Friday, August 26, 2005

What's Happening?

RTS 04

Even though things may seem to be slow here at the (unofficial) GMT Blog, things are progressing in a positive manner. It's just that - like the evolution of the RTS 03 to 04 - they're not nessecarily visible at a quick glance.

However, I hope that they'll continue to improve your visits to this page.


While the use of broadband continues to grow in residential households, there are still many who do not have a high-speed connection - myself included. As a result, rather than bombarding you with half a page of text, and 4 or more pictures, I've adopted an expandible post link.

If you're reading this, you've just experienced it. On the bottom of each post will be a link entitled 'Read More'. Click on that, and you'll be transfered to the permanent page for that posting, which contains the article and photography in their entirety.

All new postings will have no more than two photographs before the 'cut', as to lower initial load times for all visitors. A maximum of four posts initially load on the main page. Any others can be accessed through 'Recent Postings' and 'Archives' on the right-hand sidebar.

I've also gone ahead and eliminated the Haloscan TrackBack feature. I was hoping this would allow people to blog from this site, yet it offered more drawbacks than solutions - particuarly in terms of posting comments.

The Blogger comment system has been re-instated, and available at your whim. Click on the 'Comments' link at the end of each post, and a window shall pop-up for viewing old notes and creating your own.

You don't have to be a Blogger member to post a comment; however, you do need complete a word check before finalizing posting. No big deal. Perhaps someday I'll include spam robots in the site's demographics, but not at this time.

I'd really like to know what your opinion of the site is. I've tried to strike an attractive blend that's easy to use, read, and quick to load. While it seems to work for me, I'd like to know what your take on it is.

Feel free to comment on any thing that gets your attention.

Thanks again,

Evan

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Monday, August 22, 2005

G Van Diesel; Class C Presentations Available

2006 G-VansThere's been a fair amount of interest in the new availability of the Duramax 6.6 liter turbo-diesel V8 in the 2006 G-Vans. While (for some strange reason) limited to 2500 and 3500 cargo vans only, it's a sign that GM's expanding the market horizons of these vans - as they hoped to do when launching the new Class C cutaway chassis last year.

Savana w/ Duramax Unigraphics Model
While most information on these trucks is relatively scarce, you can now view and download Powerpoint presentations given on these trucks during their introduction at the Wentzville Assembly Plant.

Front-Of-Dash Revisions
Perhaps the most interesting presentation is the engineering overview of the new Duramax-equipped vans. While it may seem relatively simplistic to put the Duramax into the engine bay, substantial revisions occured throughout.

Interior Revisions
While some changes, like interior trim bolsters, were relatively minor, many components, including the body's engine opening, had to be resized and redone in order to equip this engine. The largest changes took place in the vans' HVAC system, mostly due to the addition of a fuel operated heater.

The engine presentation also gives some interesting prototype photos of the Duramax installed. Additionally, it gives a few comparisons to the Ford E-Series vans equipped with the PowerStroke diesel.

Class C Chassis Changes
The oft-forgotten Class-C motorhome cutaway also has its own set of presentations, mainly to prove it has a market case, and to highlight what changes have occured to the chassis. These changes consist of frame reinforcments and mounting points, heavier duty suspension, and integration of engine and transmission oil coolers.

You may download and view the presentations from the following links:

Duramax Diesel Presentations


Class C Presentations



Read more!

Sunday, August 21, 2005

Additional Transbus References Acquired

Transbus Operating Manual

Call it paranoia or greed, but I didn't want to count chickens until they've hatched.

The (unofficial) GMT Blog has just acquired an original Drivers' Handbook to the 1973 GMC Transbus prototype. While other prototype vehicles don't usually carry operating manuals, the Transbus did - due to the fact that it would be publically tested by operators outside of GM Employees.

Kudos must go to GMT Blog reader Bob Bray, who alerted us to this item on eBay. Photos and information will be posted once it arrives.

Read more!

Friday, August 19, 2005

GM Transbus Engine For Sale

GM Transbus Detroit Diesel-Allison Gas Turbine Powerplant
While searching for any and everything related to the GM Transbus program, this interesting motor came up on Ebay.

This is a Detroit Diesel-Allison GT404 split-shaft regenerative gas turbine. This engine was primarily used for GM's experimental truck programs - notably that of the Transbus. The GM Transbus design was the only one out of three that did not utilize a conventional diesel engine.

GM Transbus Detroit Diesel-Allison Gas Turbine Powerplant
The engine is painted Detroit Diesel sage green, and features a bellhousing that mated up to an Allison automatic - in the case of the Transbus, an HT727 transmission.

GM Transbus Detroit Diesel-Allison Gas Turbine Powerplant
The seller claims that it came from a bus, and was possibly never used. While the latter claim is relatively unsubstantiated, it's very likely that this engine was designated for the Transbus program. Regardless, it's an extremely rare piece of automotive history as it stands.

You can view the Ebay auction here.

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Wednesday, August 17, 2005

Muscle Trucks


As I was admiring some clean vintage GM trucks cruising Woodward Avenue here in South-Eastern Michigan (including a very rare first-generation G-Van), I got to thinking. Is there a way for a GMC enthusiast to share the joy of a muscle car, without having to customize the truck?


It turns out that there is. And no, I'm not talking about the later 454 SS or the new VortecMAX packages. While Chevrolet had a car-based pickup intermittantly since 1959 (the popular El Camino), starting in 1971, GMC had it's own version entitled as "Sprint".


Was it simply a case of badge-engineering? Yes. But was it a true muscle car? With a car-based chassis, a 454 cu.in. V8, and a Muncie 4-speed manual - does it sound like anything else?

While the photos here show a '72 and '71 Sprint, respectively, it continued to be made through '77. In 1978, the El Camino moved to the G-body Malibu. When this change occured, the GMC version was renamed Caballero.


Regardless, if you're interested in a really sweet '71 Sprint, take a look at Dan Guir's extremely rare '71 Sprint SP 454. His research on these muscle trucks is virtually second to none.

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Monday, August 15, 2005

Back to the Boondocks



For those enthralled with scale modelling, this may be of interest to you.

Thanks in part to the efforts and expenditure of The Model King, the long-lost 1/25 scale "Boondocker" 1972 Chevrolet K5 Blazer is being re-issued by AMT.

Original issue kits have been seen reaching upwards of $50 on Ebay. Expect this kit to sell at a local hobby shop near you - or Hobby Heaven - for around $20 or less.

Read more!

Sunday, August 14, 2005

Truck Testin' - GM Trucks on the Proving Grounds

GMC General
It almost never fails that any design looks better on paper than in person. Inherent flaws, quirks, and nuances that cannot be expressed in a drawing almost always show their face in a real-world scenario. The Tacoma Narrows' Galloping Girdie, anyone?


Chevrolet Military CEMMV in RF Testing
Regardless - with this "Law of Murphy", how would one go about creating a strong, safe, and reliable truck? The answer - even with the advancement of computer-aided engineering programs - has always been real world testing.



GMC 7000 in Testing
While GM has desert proving grounds in Tempe, AZ, the main grounds have been located in Milford, MI, since 1912. While the majority of products tested there are cars and light-duty trucks, products as diverse as heavy duty trucks, buses, military vehicles, and even earthmoving equipment have been put through their paces on the grounds.

GM Milford Proving Grounds
While the existing grounds could accomodate such vehicles, GM still built special facilities for such testing. The largest of which was built for GM Truck & Coach. The entire lower ring by numbers 23 and 24 was dedicated for truck usage. The facilities in the inner area were Truck & Coach facilities, and allowed for engineers to wrench on vehicles on site, as opposed to back in Pontiac.

GMC Astro EMC Testing
To accomodate the large size of these products, test facilities - for criteria like emissions and EMC - were installed at this location. The photo above shows the very large coils used for EMC testing on an Astro 95.

Additionally, a test facility for earthmoving equipment was established at the left end of the road strip at number 9. Facilities were installed here for dynomometers, scraping, bulldozing, and truck loading.


GMC RTS-II 04 in Milford
But if you're thinking that you've now come across up-to-date maps of a super-secret area, that's not the case. Since selling the heavy-duty truck and coach operations off, GM hasn't had much of a need for the specialized truck course, and have since put it to different use. This portion of the GM Tech Center now hosts a replica of segments of Germany's famed Nurburgring. The new curvacious, swooping course also has a nickname of the "Toiletbowl" thanks to its physical attributes.

Read more!

Wednesday, August 10, 2005

Developing Pieces

I really appreciate the massive patronage here at the (unofficial) General Motors Truck blog. 860 some-odd visitors in a little over two and a half months is, in my mind, stellar for a relatively young and unknown site.

With that in mind, I will do two things simultaneously. I'd first like to apologize for the lack of posting over the last week, and I'd secondly like to give previews of upcoming features that should (fingers crossed) grace these virtual pages within a week.



The History of the GM-Isuzu Cabovers (to be in 3 or 4 parts)

1974 GM Transbus Prototype - Milford Proving Grounds Towing

The GMC Transbus


I'll also keep any breaking GM Truck related news posted on here as it develops.

I'd also like to take this chance to ask for your assistance. If you, or anyone you know, worked at General Motors Truck & Bus or Truck & Coach, and would be willing to recount their experiences, please let me know. In particular, those with experiences involving the Transbus or RTS coach are desired at this time; yet all will be welcome - and acknowledgement will be made.

Thanks again for your support.

-Evan

Read more!

Saturday, August 06, 2005

Towing The Transbus

Transbus Modular Frame inside GM Truck & Bus Prototype Garage
I wasn't sure exactly what I was going to find at the Detroit Public Library's National Automotive Historical Collection's "Duplicates Sale", let alone if I was to find anything that would lend itself useful to this blog.

Somewhere between scroungning through boxes of Brazilian Chevrolet medium duties (to be posted shortly), and paging through 20 pristine copies of introductory brochures for the GMC General, I found a set of 8 photographs, all stapled underneath a photograph of an odd-looking frame.

GMC Transbus Prototype Towing Frame
Turns out, this frame has much to do with the forebears of the RTS bus....

The stack of photos, 9 in total, detail tests performed at GM's Milford Proving Grounds in 1974. The main purpose was to detail and evaluate a new towing system, designed for the prototypical Transbus design.

1974 GM Transbus Prototype - Milford Proving Grounds Towing

The tow system consisted of two frames. The lower frame was long and rectangular; it connected behind the front suspension, and also supported the bus just ahead of the front wheels.

1974 GM Transbus Prototype - Milford Proving Grounds Towing

The upper frame was "A"-shaped, and ran from the hitch of a tow truck, to connectors in the front bumper of the bus. What mounts this connected to is still unknown.

1974 GM Transbus Prototype - Milford Proving Grounds Towing
1974 GM Transbus Prototype - Milford Proving Grounds Towing

The remainder of the photos show the Transbus (towed by a Milford PG-owned GMC HI-9500) being lugged around sections of the track. No captions are included with these shots, so they're most definately internal engineering photographs.

1974 GM Transbus Prototype - Milford Proving Grounds Towing
1974 GM Transbus Prototype - Milford Proving Grounds Towing
1974 GM Transbus Prototype - Milford Proving Grounds Towing
1974 GM Transbus Prototype - Milford Proving Grounds Towing

Thanks to an apparently eager photographer, The (unofficial) GMT Blog is now able to display various shots and angles of this rarely-known prototype.

1968 GM RTX Prototype

Conversely, we are also able to compare it to the similar-looking information regarding the RTX, GM's transit-bus prototype from 1968. While the body is virtually identical, the RTX differs in having tri-rectangular headlamps (similar to production RTS units), single turnsignals in the bumper grilles (as opposed to duals in the Transbus), and a full-length passenger compartment, thanks to the underfloor-mounted gas turbine engine.

And as for that opening photo - that was purchased seperately, but it is almost certain that it is of an RTX/Transbus prototype. Taken in the GM Truck & Coach engineering bays in Pontiac, MI, it's dated in 1970. The frame in the foreground bears the same welded-module assembly that the RTS carries, but also sports a lower step-in height. Look closely at the depth of the door/step of the rear door in the shot.

The (unofficial) GMT Blog is currently researching more into the background of the RTX, Transbus, and RTS. Additional information will be posted as it develops.

Read more!

Wednesday, August 03, 2005

What $30 Million Buys You


GM announced today that it's spending $30 million to upgrade its' Wentzville, Missouri plant's stamping capabilities.

The whopping sum buys the factory two new presses, which will be installed starting later this year, and continuing through 2007.

Wentzville built 173,600 GMT 610 vans, which include the GMC Savana and Chevrolet Express. Demand is estimated to arise in coming months, with the new availability of the Duramax 6.6L turbo-diesel V8 in 2500 and 3500 cargo vans, and the new Chevrolet/Workhorse Class C motorhome cutaway.

Read more!

First Official Lambda Platform Photograph



Albeit it's a poor shot, the above photo is the first official GM-released picture of it's new Lambda production-ready platform.

While GM plans to have variants of this truck sold as both a GMC and a Buick, Lambda will also be sold by Saturn as the Outlook. This picture, coupled with rashes of spy photos like the one below, not only shows styling cues incorporated on other upcoming Saturns (Aura & Sky), but also perhaps hints that the Outlook may be the first version to reach the market.

(Photo by Edmunds/KGP/Autobild)

Given that the Outlook will be around the size of the current CSV minivans, don't be surprised if the Outlook replaces the Relay in the near future. Expect V6 and V8 powertrains, and a hybrid electric system sometime after its initial launch.

Read more!