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Topic: How important is the transmission retarder? (Read 4411 times) previous topic - next topic

Re: How important is the transmission retarder?

Reply #50 –
Quote from: Caflashbob –
My cruise stays on.
Bob, the way FT wired it the retarder will cause the brake lights to come on when activated.  That will kick out the cruise.  If yours does not do that, then it is the only one I know of that does it that way.  It was the same on all three of my coaches.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: How important is the transmission retarder?

Reply #51 –
Was about $500 for part, easy install I was told
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: How important is the transmission retarder?

Reply #52 –
Quote from: John S –
Bob, the way FT wired it the retarder will cause the brake lights to come on when activated.  That will kick out the cruise.  If yours does not do that, then it is the only one I know of that does it that way.  It was the same on all three of my coaches.

My coach does not turn off the cruise when the retarder kicks on to hold the set cruise speed. My little Mercedes will apply the brakes while on cruise without activating the brake lights when descending a hill.

I was nicked by the rozzers once while on cruise control as the car ran past the set cruise speed on a descent and I hadn't noticed it. 
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: How important is the transmission retarder?

Reply #53 –
So to further understand "joystick retarder" operation.

Is it true that if you have the joy stick one or two clicks back, the retarder starts slowing you as soon as you take your foot off the throttle. That would mean that there is less coasting to a stop, which I generally do a lot of ?

Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: How important is the transmission retarder?

Reply #54 –
Quote from: Bob & Sue –
So to further understand "joystick retarder" operation.

Is it true that if you have the joy stick one or two clicks back, the retarder starts slowing you as soon as you take your foot off the throttle. That would mean that there is less coasting to a stop, which I generally do a lot of ?


Yes, exactly.  It give you a variable coasting rate, with having 6 positions of ever increasing "resistance"?  I too like to coast, and often just drop a hand on the stick, as I flow with traffic, and watch ahead for lights.  Same when topping a hill, and lift off the throttle.  The stick allows me to set my downhill speed, a click at a time, to slow or increase my speed slightly.
Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)

Re: How important is the transmission retarder?

Reply #55 –
Quote from: John S –
Bob, the way FT wired it the retarder will cause the brake lights to come on when activated.  That will kick out the cruise.  If yours does not do that, then it is the only one I know of that does it that way.  It was the same on all three of my coaches.

My understanding is that my coach along with a lot of others had a wire fall off of a relay under the dash that allows vthis.

My ca sales buddy at Foretravel of California roger Tischendorf mentioned the mod he called "neat"

Not that anyone would do such a thing on purpose(nudge, nudge) of course but I am not motivated to research how to reconnect this fortunate circumstance.

Used to mod the 3176 cats in Marquis with "customer preference" software which worked exactly the same way and turned on the brake lights.

Maybe my lights are not on but I thought they were?  Think I checked it once and the did come on under cruise when the retarder engaged.

Gently tugging me back then off then back on.  Sure is easier and in my opinion safer to be able to maintain an exact speed down hills in my experience governed by the lever. 

Can probably text my X Foretravel dealer mechanic buddy guru to find out what exactly is going on but I am paranoid someone here might think the idea is wrong to modify the system like this. 

Do whatever you feel comfortable with.

If you drove mine you would want it badly IMO.

"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: How important is the transmission retarder?

Reply #56 –
Quote from: Bob & Sue –
Is it true that if you have the joy stick one or two clicks back, the retarder starts slowing you as soon as you take your foot off the throttle. That would mean that there is less coasting to a stop, which I generally do a lot of ?

Yes. That's one of its several useful features.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: How important is the transmission retarder?

Reply #57 –
About 300.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: How important is the transmission retarder?

Reply #58 –
I've now had some experience with both the Jacobs type brake and the retarder both working with Cat engines.  Unfortunately for this discussion my jury is still out.

My old coach (Vogue) had a jake brake on a bigger Cat (11 liter 3176) and was very effective.  It operated much like the retarder in that when it was turned on lifting off the throttle immediately applied the jake brake at whichever setting (hi/lo) was selected by switch.  The arresting power was substantial because it turned that 11 liter Cat into a huge air compressor brake.  I never found a downhill it couldn't manage easily.

The disadvantage of the jake was because of its arresting power.  At times it was a bit heavy-handed with its braking.  For example, when exiting a highway it would pull the coach to a crawl on the exit ramp and I could get into a bit of a yo yo effect to modulate exit speed.

Since the exhaust was fully muffled even at higher speeds/rpms the jake made very little noise.  Several city cops that I queried told me not to worry about using it in town as the typical ordinance is directed at the bigger truck engines without adequate muffling.

On my new (to me) FT I have the retarder on a 1997 40' U295 with a ~7 liter Cat 3126.  Perhaps because it is an overall smaller drive train the retarder does not seem to have the same level of arresting power as my previous jake brake experience.  This may also be an operator experience issue as the jake was tied to the transmission controller and immediately dropped 2 gears when engaged where the retarder doesn't.

The retarder is certainly smoother and one can modulate the amount of braking much more precisely than the jake, avoiding the yo yo issue on exit ramps.  It is also quieter, but since the muffled jake only produced a little puttering sound that's not a significant issue.  I think that with judicious use of transmission gear, retarder level and service brake it will serve equally well.

Quote from: lenspeiser –
I have driven both in different applications and now I have a question about them. I have used a Jake brake in a Cummins powered Mack with a thirteen speed eaton trans with a four speed brownie. The Jake was awesome coming off mountain passes in Colorado loaded to the gills with prestress concrete. But that was standard transmission. It was going to stay in whatever gear I chose until the gear box melted down.

I love the retarder in our FT. But that is an automatic transmission that will ( to my understanding) always want to up-shift as the engine hits higher RPM's. Not having driven an Allison with a Jake, does it just pop up through the gears until it gets to top gear and then use the engine compression to slow down?

Seems to me, having both would be the ideal if you do a lot of high mountain cruising.

Thanks,
Len

Len,

Both Jake and retarder can be used in the same way (and generally with the same rough rule).  The Allison trans can be locked into a maximum gear using the up/down arrows on the pushbutton control panel (or with a lever).  If the down arrow is used to drop the trans to, say, 3 it won't upshift any higher (one exception might be on electronically controlled engines coupled to the trans IF a situation would redline the engine).  Just like with a manual trans the basic rule is come down in the same gear you went up.

With the electronically-controlled 3176 "talking" with the Allison I never experienced an upshift with the Jake brake on, but just the opposite.  Once engaged the Jake wanted to push the trans to lower gears as the coach slowed, dropping all the way to 2nd gear where it finally kicked out.  It was also "smart" enough to factor in speed.  If I lifted off the throttle at full highway speed it would not drop to a lower gear if it would overspeed the engine.

I seem to remember reading somewhere (which at my age I can't remember the source) that it was not advisable to couple a retarder and a Jake, which made sense to me.  Basically, the engine, with Jake on, is trying to put negative power through the trans to the wheels and the retarder is applying a drag to that negative power.
Regards

1997 U295 40 with CAT 3126

Re: How important is the transmission retarder?

Reply #59 –
FYI.  FT just measured all my pads and found they were at 70% of original thickness at 160,000 miles.  I use my retarder all the time except in stop and go traffic or when I want to coach.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: How important is the transmission retarder?

Reply #60 –
If they all were about the same thickness your in good shape.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: How important is the transmission retarder?

Reply #61 –
Hi All,
  My 1997 U320 did not come with the joystick to control the retarder. Roger Sellers, TN RV, gave me a joystick kit. The kit came with a relay, that if left out, allowed for cruise on when brakes lights were on. The directions that came with the kit explained it all. It was a simple installation.
Raymond
Raymond & Babette Jordan
1997 U 320
1998 Ford Explorer XLT

Re: How important is the transmission retarder?

Reply #62 –
Quote from: Raymond Jordan –
Hi All,
  My 1997 U320 did not come with the joystick to control the retarder. Roger Sellers, TN RV, gave me a joystick kit. The kit came with a relay, that if left out, allowed for cruise on when brakes lights were on. The directions that came with the kit explained it all. It was a simple installation.
Raymond

Yes.  Old trick.  You will find it hard to wipe the grin off of your face after driving one setup this way.
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4
 

Re: How important is the transmission retarder?

Reply #63 –
My old coach (Vogue) had a jake brake on a bigger Cat (11 liter 3176) and was very effective.  It operated much like the retarder in that when it was turned on lifting off the throttle immediately applied the jake brake at whichever setting (hi/lo) was selected by switch.  The arresting power was substantial because it turned that 11 liter Cat into a huge air compressor brake.  I never found a downhill it couldn't manage easily.

The disadvantage of the jake was because of its arresting power.  At times it was a bit heavy-handed with its braking.  For example, when exiting a highway it would pull the coach to a crawl on the exit ramp and I could get into a bit of a yo yo effect to modulate exit speed.


BillO while this is obviously not important anymore I ran across the same thing and the CAT man mentioned a three position switch available.  2,4 or 6 cylinder Jake
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4