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Topic: New owner of a 94 U225 seeking grade climbing advice (Read 3399 times) previous topic - next topic

New owner of a 94 U225 seeking grade climbing advice

Hello fellow Foretravelers!

I just bought a 94 U225. The coach was in great shape being stored in a hanger most of it's life.  The PO is now deceased and I bought it from his daughter. PO was a pilot/small plane builder so I'm not surprised at how clean the coach is at 115K miles but it's been sitting quite a few years. I am told a local mechanic/neighbor comes out monthly to start it and check the batteries and fluids. I drove it around the neighborhood but didn't go too far as the tires have aged out (even thought they look band new). Started right up, idles and drives smooth. I bought it because the interior is spotless and the undercarriage/frame is like new. All house systems seem to work.

So here's the question: I have to drive it 40 miles downhill into Henderson NV for new tires right after I pick it up and then drive it back to SoCal over some sizable grades, 6% for six miles is one of them. I see the engine is a Cummins 5.9, small and not a lot of power for this size rig. All the gauges work and I don't want to burn this engine up while trying to climb out of Nevada. Any driving tips you experienced drivers want to share?  It's a four speed so I assume I'll be climbing slowly but not sure where to hold the RPM to maintain cooling. What gear do you typically climb in? Same question going down a 19 mile grade past Baker CA. I am upgrading from a 31 foot airstream motorhome with a little Isuzu that climbed really well since that coach is half the weight of the U225.  This motor sounds really under powered for the weight of a U225.  The Alison specs look like it's almost maxed out at 250HP so that doesn't help.  I tend to over analyze things so I welcome any wisdom from experience you can share. Did I just buy the wrong coach for west coast travel?

Thanks for any wisdom you can share.  ^.^d

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #1 –
Welcome to Foretravel ownership and to the Foreforum.  I cannot help with the questions you posed but it certainly sounds like you found a hidden jewel.  One thing about this forum, we love to see pictures of your coach and of any projects you undertake.  Again, welcome. 

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #2 –
I believe (you can confirm by contacting Cummins with your engine serial number) that governed RPM is 2,500.

So, under extended climbing, I would hold it around 2,200 RPM with throttle just a little short of WOT (Wide Open Throttle). If coolant temperature rises more than 10 degrees F, back off throttle/downshift.

If you ever get into the front of the motor, look up "killer dowel pin".  Some labor, but very few $$ in parts.

With the U225, you will want to check Ride Height.  It is adjustable and can affect ride as well as component longevity.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #3 –
Welcome to the Forum!  Always glad to have new GV owner's join the group.

With a '94 U225 you got the small Cummins and a 4-speed trans.  This engine/trans combo typically will NOT have any auxiliary braking device, although Foretravel made a lot of one-off unusual combinations in those days.  One model year later, the Allison hydraulic transmission retarder started showing up on various Foretravel models. 

Our coach is a '93 U280, which also came from the factory sans extra braking assistance.  One of the (4) previous owners of our coach installed a aftermarket exhaust brake.  We have found this device to be very helpful when dealing with long downgrades.  We have made multiple trips over the Rocky Mountains, from TX to Oregon, descending the steep downhill sections with zero "white knuckle" incidents.

Since the previous driver of your new-to-you coach was into airplanes (mechanically minded), and lived in a hilly area, it is possible they might have fitted the coach with an exhaust brake.  You can either ask about it, or just lift the mattress platform and take a look.  The exhaust brake (if present) would be installed in the exhaust pipe somewhere between the turbo and the muffler.

The D-Celerator exhaust brake on our coach is long out of production, but there is a similar device called the PACBRAKE PRXB still being produced.  See the links below if interested in this subject.

Exhaust Brake Experience

D-Celerator Exhaust Brake

Pacbrake:Exhaust Brakes

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #4 –
We had a '93U225 36'. When climbing, we noted the gear the transmission chose, and used that gear to descend, applying the brake intermittently to avoid overheating the brakes.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #5 –
Congrats on your purchase and welcome to the forum. I have a 1993 U225 and have made the Baker to Henderson trip and back a couple times. As Brett said, keep your RPM about 2,200 and watch your heat gauge when climbing. Stay in the right hand lane and back off the throttle and downshift as necessary to keep the engine temp around 200. When descending, apply your brakes periodically to keep a safe distance from the vehicle in front of you.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #6 –
Alot of good advice , I will add some of my experience from having a 6V92 in our 92 U300 , granted is was a bigger 350hp and it had the Allison 4 speed .
When climbing steep grades watch you temp gauge and tac,  at 1500 rpm's downshift manually to third and see where your at . With the Detroit heat is not your friend so pulling more air thru the radiator will help with cooling..

Like Brett and others advised keep your rpm's will help.Waiting tor the tranny to shift on its own invites overheating. And the old truck drivers would go by what ever grear you go up a grade that should  be the grear you go down the hill. Good luck with your new ride and have fun.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #7 –
Keep your downhill speed around 50.  Everyone will go around you- it doesn't matter. You can stop or slow down if needed at a slower speed without overheating your brakes. It's easier on your nerves, too. Keeping your rpm's up will keep everything nice and cool.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #8 –
On the Sherman Grade coming into Bishop you will need to be much slower than 50 mph. Maybe around 35.
 6 percent grade 10 mi.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #9 –
Actually, the "best" speed of descent is at the speed/in the gear where you can maintain your speed rather than speeding up with only OCCASIONAL use of the service brakes.

Each grade is different, so there is no ideal speed that applies to all of them.

We have been on some where 5th (6 speed) was fine, and others that required 2nd.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #10 –
The trans slips always.  No lock up torque converter.  Plus the motor is smaller as you noted.  The coach has drum brakes of medium size. Rockies? Slower up. Slower down. 

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #11 –
Quote from: Caflashbob –
The trans slips always.  No lock up torque converter.
Thanks, Bob, for that info.

In that case, U225 would not be a suitable candidate for an exhaust brake.

HOWEVER, upon reconsideration, the excellent ForeForum Wiki shows the '94 U225 came with the Allison MT643 transmission.

1994 Foretravel Specifications

A quick online search brings up the MT643 spec sheet, which clearly states "automatic lockup in 3rd & 4th"

http://waghornswood.net.nz/Manuals_01_18/Vehicles/Allison_Automatic/Allison_MT_643.pdf

Is there some reason why the MT643 version used in the U225 would not include this feature?


Re: New owner of a 94 U225 seeking grade climbing advice

Reply #12 –
Quote from: Chuck & Jeannie –
Thanks, Bob, for that info.

In that case, U225 would not be a suitable candidate for an exhaust brake.

HOWEVER, upon reconsideration, the excellent ForeForum Wiki shows the '94 U225 came with the Allison MT643 transmission.

1994 Foretravel Specifications

I



A quick online search brings up the MT643 spec sheet, which clearly states "automatic lockup in 3rd & 4th"

http://waghornswood.net.nz/Manuals_01_18/Vehicles/Allison_Automatic/Allison_MT_643.pdf

Is there some reason why the MT643 version used in the U225 would not include this feature?
f you drive the coach the trans shits 3 times. A 643 would feel like it shift 4 times due to lockup. I won a dinner from the Allison man at a FMCA show long ago.  I looked at the shown 542 trans he had on a pallet and commented that it was a 4 speed hydro trans from long ago but in aluminum versus iron.  He said it was a new design.  I said the oil pan will say hydra matic on it.  We lifted it up and embossed on the pan was hydramatic.  We used to use the trans in drag racing days.

I sold these new and have seen a few owners modify the cooling system to lower perceived heating issues. Not really needed but most owners panic if the temp gauge moves off its normal position.  It will move.  Do not worry about it.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #13 –
Thanks everyone for the helpful information. I'll take it slow up and down and watch the temp gauges. The PO added a second temp gauge that I am assuming is for the Alison.

The rear tires are dated 2009 and fronts are 2004 so I'm going to make new tires a priority.  I just wish they didn't look so new but I do understand they have aged out.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #14 –
Quote from: MrLan1 –
Thanks everyone for the helpful information. I'll take it slow up and down and watch the temp gauges. The PO added a second temp gauge that I am assuming is for the Alison.

The rear tires are dated 2009 and fronts are 2004 so I'm going to make new tires a priority.  I just wish they didn't look so new but I do understand they have aged out.
I hope you are still going to Henderson for new tires before traveling the 395 to So. Cal. They can blow the tread off while looking brand new. Tires are made of petroleum now not rubber driving them keeps the tread and sidewalls soft when sitting as this coach has the tire dries out and is brittle.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #15 –
Possible the 94 had a trans switch. The torque converter lock up in mid third gear is noticeable. Like I posted a 643 will feel like it shifts 4 times. A 542 will shift three times

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #16 –
Quote from: craneman –
I hope you are still going to Henderson for new tires before traveling the 395 to So. Cal. They can blow the tread off while looking brand new. Tires are made of petroleum now not rubber driving them keeps the tread and sidewalls soft when sitting as this coach has the tire dries out and is brittle.
Absolutely.  Would not want to be stuck out on the 15 with a blown tire in the middle of nowhere.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #17 –
I have the 643 and steep climb in top of third . Ease off if needed to stay in third lock . The trans temp will not get hot if the trans is in lockup. 
Down hill , leave in third and take your time. Short strong push on the  brakes to slow and release to cool them.

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #18 –
Quote from: Chuck & Jeannie –

Since the previous driver of your new-to-you coach was into airplanes (mechanically minded), and lived in a hilly area, it is possible they might have fitted the coach with an exhaust brake.  You can either ask about it, or just lift the mattress platform and take a look.  The exhaust brake (if present) would be installed in the exhaust pipe somewhere between the turbo and the muffler.

The D-Celerator exhaust brake on our coach is long out of production, but there is a similar device called the PACBRAKE PRXB still being produced.  See the links below if interested in this subject.

Exhaust Brake Experience

D-Celerator Exhaust Brake

Pacbrake:Exhaust Brakes

And we can update this topic that there is an exhaust brake  ^.^d  in the coach

94 U225 mystery dash button ???

Re: New owner of a 94 U225 seeking grade climbing advice

Reply #19 –
Note:  The back pressure a/any exhaust brake produces MUST be within the specs for your particular engine.

Not just Cummins, but Caterpillar as well.  I know that on the Caterpillar 3116, engines produced before a certain serial number were limited to right at half the back pressure of the subsequent engines.  So, do not assume that all Cummins B engines are the same-- verify with Cummins.