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Does "S" shift position have engine braking?

6
6cuda6@gmail.com
Tue, Jul 27, 2021 7:54 PM

Curious....do the "S" shift position have engine braking as well, unlike "D" which just seems to freewheel the engine on decel down hill.

Reason i ask is i have a long steep grade that really taxes the brakes and i would prefer to just use the engine to help things.

Rich Mondor,

Brockville, ON

77 Hughes 2600

Curious....do the "S" shift position have engine braking as well, unlike "D" which just seems to freewheel the engine on decel down hill. Reason i ask is i have a long steep grade that really taxes the brakes and i would prefer to just use the engine to help things. -- Rich Mondor, Brockville, ON 77 Hughes 2600
KV
Keith V
Tue, Jul 27, 2021 8:01 PM

Yes.
Slow the coach with the brakes before putting it in S and then use engine braking to keep you there.
Do not use S to reduce speed, only to maintain it.
IF the coach does start to go faster than you're comfortable with, then apply the brakes to get the speed back under control.
Use the brakes as little as possible but no less.

Keith Vasilakes
Mounds View MN
76 exRoyale
MicroLevelhttp://www.gmcmotorhomemarketplace.com/vasilakes/microlevel_intro.pdf


From: 6cuda6@gmail.com 6cuda6@gmail.com
Sent: Tuesday, July 27, 2021 2:54 PM
To: gmclist@list.gmcnet.org gmclist@list.gmcnet.org
Subject: [GMCnet] Does "S" shift position have engine braking?

Curious....do the "S" shift position have engine braking as well, unlike "D" which just seems to freewheel the engine on decel down hill.

Reason i ask is i have a long steep grade that really taxes the brakes and i would prefer to just use the engine to help things.

Rich Mondor,

Brockville, ON

77 Hughes 2600


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Yes. Slow the coach with the brakes before putting it in S and then use engine braking to keep you there. Do not use S to reduce speed, only to maintain it. IF the coach does start to go faster than you're comfortable with, then apply the brakes to get the speed back under control. Use the brakes as little as possible but no less. Keith Vasilakes Mounds View MN 76 exRoyale MicroLevel<http://www.gmcmotorhomemarketplace.com/vasilakes/microlevel_intro.pdf> ________________________________ From: 6cuda6@gmail.com <6cuda6@gmail.com> Sent: Tuesday, July 27, 2021 2:54 PM To: gmclist@list.gmcnet.org <gmclist@list.gmcnet.org> Subject: [GMCnet] Does "S" shift position have engine braking? Curious....do the "S" shift position have engine braking as well, unlike "D" which just seems to freewheel the engine on decel down hill. Reason i ask is i have a long steep grade that really taxes the brakes and i would prefer to just use the engine to help things. -- Rich Mondor, Brockville, ON 77 Hughes 2600 _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options:
JR
John R. Lebetski
Tue, Jul 27, 2021 8:46 PM

All gears on the TH 425 have engine braking. It’s just not very noticeable in 3rd.  If you switch to a higher numerical gear final drive, all 3
gears will have more engine braking.

John Lebetski
Woodstock, IL
77 Eleganza II

All gears on the TH 425 have engine braking. It’s just not very noticeable in 3rd. If you switch to a higher numerical gear final drive, all 3 gears will have more engine braking. -- John Lebetski Woodstock, IL 77 Eleganza II
R
Richard
Tue, Jul 27, 2021 8:51 PM

Rich,

The 1977 Motorhome Operating Manual section on the Automatic Transmission (p18) reads:

SUPER RANGE "S" - Used when super performance is needed for increased acceleration in traffic, hill climbing, or "Engine Braking" down-hill.  The
selectors lever may be moved from "D" to "S" and Vice verse, under most operating conditions. "SUPER" should not be used at speeds above 75 MPH.

And in the highlighted note:
CAUTION
Before descending a step or long grade, down a mountain or hillside, reduce speed and shift into a lower gear. Use the lower gear ranges to control
speed.

It's interesting that the manual states LOW "L" may be used at any speed (it doesn't have the top speed limitation as above), and the transmission
only shifts automatically into L below ~40 MPH.

Richard

'77 Birchaven TZE...777;
'76 Palm Beach under construction;
‘76 Edgemonte waiting its turn

Rich, The 1977 Motorhome Operating Manual section on the Automatic Transmission (p18) reads: SUPER RANGE "S" - Used when super performance is needed for increased acceleration in traffic, hill climbing, or "Engine Braking" down-hill. The selectors lever may be moved from "D" to "S" and Vice verse, under most operating conditions. "SUPER" should not be used at speeds above 75 MPH. And in the highlighted note: CAUTION Before descending a step or long grade, down a mountain or hillside, reduce speed and shift into a lower gear. Use the lower gear ranges to control speed. It's interesting that the manual states LOW "L" may be used at any speed (it doesn't have the top speed limitation as above), and the transmission only shifts automatically into L below ~40 MPH. Richard -- '77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemonte waiting its turn
6
6cuda6@gmail.com
Tue, Jul 27, 2021 11:01 PM

Richard RV wrote on Tue, 27 July 2021 16:51

Rich,

The 1977 Motorhome Operating Manual section on the Automatic Transmission (p18) reads:

SUPER RANGE "S" - Used when super performance is needed for increased acceleration in traffic, hill climbing, or "Engine Braking" down-hill.  The
selectors lever may be moved from "D" to "S" and Vice verse, under most operating conditions. "SUPER" should not be used at speeds above 75 MPH.

And in the highlighted note:
CAUTION
Before descending a step or long grade, down a mountain or hillside, reduce speed and shift into a lower gear. Use the lower gear ranges to
control speed.

It's interesting that the manual states LOW "L" may be used at any speed (it doesn't have the top speed limitation as above), and the transmission
only shifts automatically into L below ~40 MPH.

Richard

Very interesting....

--
Rich Mondor,

Brockville, ON

77 Hughes 2600

Richard RV wrote on Tue, 27 July 2021 16:51 > Rich, > > The 1977 Motorhome Operating Manual section on the Automatic Transmission (p18) reads: > > SUPER RANGE "S" - Used when super performance is needed for increased acceleration in traffic, hill climbing, or "Engine Braking" down-hill. The > selectors lever may be moved from "D" to "S" and Vice verse, under most operating conditions. "SUPER" should not be used at speeds above 75 MPH. > > And in the highlighted note: > CAUTION > Before descending a step or long grade, down a mountain or hillside, reduce speed and shift into a lower gear. Use the lower gear ranges to > control speed. > > It's interesting that the manual states LOW "L" may be used at any speed (it doesn't have the top speed limitation as above), and the transmission > only shifts automatically into L below ~40 MPH. > > Richard Very interesting.... -- Rich Mondor, Brockville, ON 77 Hughes 2600
6
6cuda6@gmail.com
Tue, Jul 27, 2021 11:03 PM

Thanks guys...i will for sure downshift after speed reduction....my hope is actually to downshift even before entering the hill as its very close to
the entrance to the campsite.

Rich Mondor,

Brockville, ON

77 Hughes 2600

Thanks guys...i will for sure downshift after speed reduction....my hope is actually to downshift even before entering the hill as its very close to the entrance to the campsite. -- Rich Mondor, Brockville, ON 77 Hughes 2600
JR
John R. Lebetski
Tue, Jul 27, 2021 11:20 PM

I remember from TH400 Corvettes you could try to grab first manually at speeds above the 1-2 shift point but it would lock you out until speed was
acceptable. The TH350s would not lock you out. The TH425 is of course kin to the 400.

John Lebetski
Woodstock, IL
77 Eleganza II

I remember from TH400 Corvettes you could try to grab first manually at speeds above the 1-2 shift point but it would lock you out until speed was acceptable. The TH350s would not lock you out. The TH425 is of course kin to the 400. -- John Lebetski Woodstock, IL 77 Eleganza II
KV
Keith V
Tue, Jul 27, 2021 11:22 PM

I do t know, i remember getting reverse at 60mph. That was exciting!


From: John R.Lebetski gransport7087@gmail.com
Sent: Tuesday, July 27, 2021 6:20:13 PM
To: gmclist@list.gmcnet.org gmclist@list.gmcnet.org
Subject: [GMCnet] Re: Does "S" shift position have engine braking?

I remember from TH400 Corvettes you could try to grab first manually at speeds above the 1-2 shift point but it would lock you out until speed was
acceptable. The TH350s would not lock you out. The TH425 is of course kin to the 400.

John Lebetski
Woodstock, IL
77 Eleganza II


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I do t know, i remember getting reverse at 60mph. That was exciting! ________________________________ From: John R.Lebetski <gransport7087@gmail.com> Sent: Tuesday, July 27, 2021 6:20:13 PM To: gmclist@list.gmcnet.org <gmclist@list.gmcnet.org> Subject: [GMCnet] Re: Does "S" shift position have engine braking? I remember from TH400 Corvettes you could try to grab first manually at speeds above the 1-2 shift point but it would lock you out until speed was acceptable. The TH350s would not lock you out. The TH425 is of course kin to the 400. -- John Lebetski Woodstock, IL 77 Eleganza II _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options:
R
Richard
Wed, Jul 28, 2021 12:02 AM

Keith V wrote on Tue, 27 July 2021 16:22

I do t know, i remember getting reverse at 60mph. That was exciting!

Don't leave a guy hanging, Keith - what the hell happened???

Richard

--
'77 Birchaven TZE...777;
'76 Palm Beach under construction;
‘76 Edgemonte waiting its turn

Keith V wrote on Tue, 27 July 2021 16:22 > I do t know, i remember getting reverse at 60mph. That was exciting! Don't leave a guy hanging, Keith - what the hell happened??? Richard -- '77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemonte waiting its turn
KV
Keith V
Wed, Jul 28, 2021 2:24 AM

Ha ha ha, the Olds 442 did a LOT of engine braking, the rear tires squealed like nothing Ive ever heard before.
But the transmission and all parts seemed no worse for wear!


From: Richard birchaven77@gmail.com
Sent: Tuesday, July 27, 2021 7:02 PM
To: gmclist@list.gmcnet.org gmclist@list.gmcnet.org
Subject: [GMCnet] Re: Does "S" shift position have engine braking?

Keith V wrote on Tue, 27 July 2021 16:22

I do t know, i remember getting reverse at 60mph. That was exciting!

Don't leave a guy hanging, Keith - what the hell happened???

Richard

--
'77 Birchaven TZE...777;
'76 Palm Beach under construction;
‘76 Edgemonte waiting its turn


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Ha ha ha, the Olds 442 did a LOT of engine braking, the rear tires squealed like nothing Ive ever heard before. But the transmission and all parts seemed no worse for wear! ________________________________ From: Richard <birchaven77@gmail.com> Sent: Tuesday, July 27, 2021 7:02 PM To: gmclist@list.gmcnet.org <gmclist@list.gmcnet.org> Subject: [GMCnet] Re: Does "S" shift position have engine braking? Keith V wrote on Tue, 27 July 2021 16:22 > I do t know, i remember getting reverse at 60mph. That was exciting! Don't leave a guy hanging, Keith - what the hell happened??? Richard -- '77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemonte waiting its turn _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options: