Trip Report: Boise to Toledo with the Manny 6.5TD conversion

[XPlorID]

Boise to Henry's Lake (ID), crawl thru Yellowstone, up and over the Bighorns to Sheridan and I-90, then lost the fuel pump near Gillette WY. Spent
the next day fixing that (thanks Platinum Diesel Service!) and the sewer pipe that the tow driver broke. Stop in the Black Hills, then across SD, MN,
WI, IL, IN, and into Toledo OH.

Just about 2000 miles, 75-80mph whenever I could, about 13mpg, exactly what Bill Hubler told me to expect with the diesel.

Now in Toledo for a week or so, anybody in the area give me a shout while I am here.

I need an alignment check and tire rotation if anybody has a competent shop in NW Ohio - SE Michigan, and I need dash AC service before I head back.

Great trip so far, and really pleased with the diesel performance. With a 2.73 or 2.76 (cannot recall, but gearing out of an Eldorado) final drive
it's a slug off the line, but really wakes up on the road. Not noisy, not smelly unless you spill diesel fuel (I did of course). No vapor lock, no
overheating in slow or stopped traffic (like in Yellowstone), and the coach ran stronger after the fuel pump replacement, so that had likely been
weeping for a while.

See the USA...

Jeff
--
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back

 

[Russell]

Jeff,
Its good to hear that the diesel is performing well. How are your tranny temps running with the diesel and the 2.73 final drive? How big is your
transmission cooler? Is Cinnabar in Sandusky close enough to you for the work you need done? I hope you share some pictures from your trip.

Safe Travels.
Russell
--
Russell Keith,
1978 E2 "Harry" 403 (still carbureted), Danny Dunn Tranny, Thorley, Stock Brakes w/Remote Vacuum Brake Booster, Quad Bags, Dakota Digital Dash, 6.5 kW
Onan, Dunedin, Florida

 

[XPlorID]

Thanks for the note Russell. Sandusky is not far, thanks for that reminder. Transmission cooler is from Manny, I think a bit bigger than the one on
the Applied website but not sure. Trans temps? No idea - I do not have a gauge and with the tranny turning that slowly in this setup it is not a
primary concern, but really might be good to compare to others so I'll put trans temp gauge on the list, just not first.
Ahh Toledo - clouds, humidity, mosquitoes - just like I remember it. Actually, a great place to be from.
Jeff
--
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back

 

[john r. lebetski]

Cinnabar is Sandusky Mi, not Sandusky Oh where the amusement park is.
--
John Lebetski
Woodstock, IL
77 Eleganza II

 

[LQQKatJon]

Chances are you will stay south on your return trip on I-90 through MN and SD.

if some chance you take I-94 north route through MN/ North Dakota, I am off MN I-94 exit 174 about 4 minutes. If you need any DIY A/C work done at
that time. I am no pro, but I have vacuum pump, gauges, duracool and r-134 on hand.


--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/

 

[scott nutter1]

Very cool !!
13 mpg. That double from what I get. Awesome!!
I had a 1992 hummer with the 6.2 diesel. 1 also got 13 mpg, that was doing 70 mph or at idle. Didn't seem to matter.
Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
installed MSD Atomic EFI
Houston, Texas

 

[john phillips]

What is engine RPM at 80 MPH? Does the Diesel like to run that fast?

On Wed, Jun 5, 2019 at 3:20 PM Scott Nutter via Gmclist <

> Very cool !!
> 13 mpg. That double from what I get. Awesome!!
> I had a 1992 hummer with the 6.2 diesel. 1 also got 13 mpg, that was doing
> 70 mph or at idle. Didn't seem to matter.
> Scott.
> --
> Scott Nutter
> 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final
> drive, Quad bags, tankless water heater, everything Lenzi. Alex Ferrera
> installed MSD Atomic EFI
> Houston, Texas
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--

*John Phillips*

 

[XPlorID]

No tachometer on this coach so no idea of RPM at 80mph but someone here on the forum may do the math for us with a 2.73 differential ratio.
As I reported to Manny, the diesel seemed to love running 70-80 and with no cruise control (yet) it took some attention to keep it down. That may
have been different had I not been driving solo. Most of the trip across the plains included a crosswind out of the north but no headwinds, the coach
itself did not feel like it was struggling and I likely surprised a few drivers as they were passed by a 45 year old motorhome.
Jeff

--
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back

 

[Matt Colie]

> No tachometer on this coach so no idea of RPM at 80mph but someone here on the forum may do the math for us with a 2.73 differential ratio.
> As I reported to Manny, the diesel seemed to love running 70-80 and with no cruise control (yet) it took some attention to keep it down. That may
> have been different had I not been driving solo. Most of the trip across the plains included a crosswind out of the north but no headwinds, the
> coach itself did not feel like it was struggling and I likely surprised a few drivers as they were passed by a 45 year old motorhome.
> Jeff

Jeff,

You have a cruise control, you just don't know it.....
Hold the "Gas Peddle" in one place, and you have it (with some small designed in droop).
All diesel engines have to have a speed controlling system built into the fuel injection system. As they do not have a carburetor to strangle them
when they try to go faster, with the positive feedback of the torque curve they would be very difficult to drive were it not for that feature. I
could be boring and go on for another few pages that were all about diesel fuel control, but I have other things to do and people to annoy.

Matt - Not looking forward to pulling the front frame out AGAIN!
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

 

[hal stclair]

You should be @ about 2600 rpm if you are running 225x75x16 tires at 80. The 6.5 makes max torque in the 1800 rpm range and is governed @ 3400 rpm. If
you're getting 13 at 80 mph you must be running on pretty flat ground without unfavorable winds. Slow it down to the 2000< rpm and see what your
mileage does, you'll like it. The lower rpm will also quiet things down in the cab considerably. All things equal, diesel should see about 30%
improvement in economy, there's no magic there just more energy content in the fuel.
25,000+ miles on ours and most satisfied, but I'm a die hard diesel guy.
Have a Duramax and 6sp Allison in the shop now with ideas maybe for the future....
Hal

--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

 

[XPlorID]

What a great interest group. Thanks for the notes...I did not do 80mph all the way, but found the coach at that speed quite a few times and had to
back off, and the mileage estimate is just that. It would be great to know what this thing does for mileage at 65 with no winds. Not sure I will
ever find out, but it would be an interesting benchmark. Mileage was not the primary motivator for the diesel conversion, but FWIW it moves this
12,000 pounds very nicely with the TH425, a 4+ speed transmission would be another leap forward, for all of us.
Jeff
--
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back

 

[adolph santorine]

Hal:

What’s the HP and Torque numbers on your diesel?

Also, is the transmission a 3, 4, 5 or 6?

Mostly curiosity.

Dolph

DE AD0LF

Wheeling, West Virginia

1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Manny Transmission

“The Aluminum and Fiberglass Mistress"

>
> You should be @ about 2600 rpm if you are running 225x75x16 tires at 80. The 6.5 makes max torque in the 1800 rpm range and is governed @ 3400 rpm. If
> you're getting 13 at 80 mph you must be running on pretty flat ground without unfavorable winds. Slow it down to the 2000< rpm and see what your
> mileage does, you'll like it. The lower rpm will also quiet things down in the cab considerably. All things equal, diesel should see about 30%
> improvement in economy, there's no magic there just more energy content in the fuel.
> 25,000+ miles on ours and most satisfied, but I'm a die hard diesel guy.
> Have a Duramax and 6sp Allison in the shop now with ideas maybe for the future....
> Hal
>
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

 

[hal stclair]

Dolph, The motor was rated 194 hp, 430 tq in stock form. I installed a Charge air cooler and had the ECM flashed to allow more boost/fuel. I've gone
from a stock 7 or 8 lbs to 13 to 15 although I try to keep it under 14. The stock programming would pull boost after about 12 seconds because of EGT's
but with a CAC I don't have that issue. In reality, I'm probably in the 240/250 hp range but the tq is most likely at or near 500. There are a few
other things like a straight through 3 1/2" exhaust (still nice and quiet), nice cool air from in front of the cooling stack that help. I'm running
the 4l80e trans which is a 4 speed with locking converter. Final drive works out to a 2.76 but you don't have the ordinary 3% converter slip. Of
course I chose to run it with GM's electronics which shift the trans at the perfect times and as a side benefit self diagnose most any problem. I've
been very happy with the results, but as I stated, I've always been a Diesel guy.
Hal

> Hal:
>
> What's the HP and Torque numbers on your diesel?
>
> Also, is the transmission a 3, 4, 5 or 6?
>
> Mostly curiosity.
>
> Dolph
>
> DE AD0LF
>
> Wheeling, West Virginia
>
> 1977 26' ex-PalmBeach
> Howell EFI & EBL, Reaction Arms, Manny Transmission
>
> "The Aluminum and Fiberglass Mistress"
>

> >
> > You should be @ about 2600 rpm if you are running 225x75x16 tires at 80. The 6.5 makes max torque in the 1800 rpm range and is governed @
> > 3400 rpm. If
> > you're getting 13 at 80 mph you must be running on pretty flat ground without unfavorable winds. Slow it down to the 2000< rpm and see what
> > your
> > mileage does, you'll like it. The lower rpm will also quiet things down in the cab considerably. All things equal, diesel should see about
> > 30%
> > improvement in economy, there's no magic there just more energy content in the fuel.
> > 25,000+ miles on ours and most satisfied, but I'm a die hard diesel guy.
> > Have a Duramax and 6sp Allison in the shop now with ideas maybe for the future....
> > Hal
> >
> > --
> > 1977 Royale 101348,
> >
> > 1977 Royale 101586, Diesel powered,
> >
> > 1975 Eleganza II, 101230,
> >
> > 1974 Eagle Bus 45',w/slideout,
> >
> > Rio Rancho, NM
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM