Just borrowing a ‘77 for a trip

[mrazekan]

Hello,

My name is Hugo. A friend let us borrow their GMCMH, affectionately known as The Miracle Whip, for a two week trip over Xmas 2020. We’re very excited to see what this RV world is all about.

I’m a mechanical engineer and mechanically inclined so our friend trusted that I’d be able to get out of any situation The Whip May get us into. I’ll be bringing my tools for sure.

We’ll be heading up through central Oregon on 97 on our way to Hood River. I’ll give a honk if I see another GMC.

Be Well

 

[nate2hall]

Just drove mine 1600 miles. I would recommended bringing a gallon of coolant, a couple quarts of oil, portable air compressor, extra airbag, grease gun for the zerks and make sure you have a bottle jack and the jack adapter to raise the rear of the coach. The coaches have a lot of moving parts but your trip should be a smooth reliable one.

 

[Matt Colie]

Hugo,

Nice to meet you, you must have a very good friend. But watch out, many have make just one short excursion and become both physically and emotionally addicted at least to motorhome travel and many to GMC/TZE specifically.

Yes, carry a grease gun, one should be in the coach's kit. The grease retention of the rear suspension sucks and the best treatment is to hit those about every thousand miles. Just a shot or two.

I don't know the area you are traveling, but this time of year, depart with provisions for three days. If the weather goes bad, hunker down and stay warm. You can even watch from the warm and observe the chaos. If you have water, food and fuel, why go out into it?
Why three days??
Because we have been stopped for a day several times. One time it took most of the second day before things were clear enough to continue. The third day is just buffer.

Don't forget enjoy the excursion.

Matt

 

[mrazekan]

Just drove mine 1600 miles. I would recommended bringing a gallon of coolant, a couple quarts of oil, portable air compressor, extra airbag, grease gun for the zerks and make sure you have a bottle jack and the jack adapter to raise the rear of the coach. The coaches have a lot of moving parts but your trip should be a smooth reliable one.

Thanks for the tips. I won’t be able to get an extra airbag in time but the rest are already in or a just added to my list.

I’m learning so much about it. Like why the leveling system was not working. Turns out, there are valves at the bag that have been shut off from the system!!

 

[mrazekan]

Hugo,

Nice to meet you, you must have a very good friend. But watch out, many have make just one short excursion and become both physically and emotionally addicted at least to motorhome travel and many to GMC/TZE specifically.

Yes, carry a grease gun, one should be in the coach's kit. The grease retention of the rear suspension sucks and the best treatment is to hit those about every thousand miles. Just a shot or two.

I don't know the area you are traveling, but this time of year, depart with provisions for three days. If the weather goes bad, hunker down and stay warm. You can even watch from the warm and observe the chaos. If you have water, food and fuel, why go out into it?
Why three days??
Because we have been stopped for a day several times. One time it took most of the second day before things were clear enough to continue. The third day is just buffer.

Don't forget enjoy the excursion.

Matt

Good to meet you Matt. I fell in love when she told me about it. Even more so when she offered to let us borrow it. I’m so excited to take this trip to see what this type of traveling is like.

I’ll be sure to pick up a grease gun. The rear suspension sounds like a drag if they need to be greased every 1k. But part of the deal I guess. I hope there aren’t other areas that are this picky.

Since we have a 4 month old and a 2.5 y.o., we already are provisioning and planning for a 3 day trip to our destination. But good call. We hit elevation on the way up to Mt. Shasta just north of Redding and stay up there on 97 all the way to the Columbia River.

I remember years back after buying a car in California we were heading north and pulled off in Redding at about 8pm. My partner at the time was tired of driving in the inclement weather and asked if we could just get a room for the night. I agreed and we checked in to some clean but basic hotel just off the freeway. 20 min later they closed I5 heading up to Shasta. 20 min after that every room in Redding was booked. A storm cell popped up out seemingly nowhere and dumped 3+ feet of snow on I5. People were stuck for three days until they cleared it. Sherrifs were bring people supplies by snowmobile! We got lucky as we would have been caught in it ourselves.

Cheers!

 

[tmsnyder]

Wow that is one very trusting friend to loan you their GMC.

Just be aware they are a 40 yo, 12000 lb FWD automobile. They stop like a 70's car used to stop at best, not great compared to a modern car. Leave plenty of room in front of you and keep your eyes well down the road.

Don't be in a rush, enjoy the trip as much or more than the destination.

Ask the owner about how often to check the oil and where it should be on the dipstick. It may burn a little and that's fine, just make sure to top it off.

Ask the owner about fuel octane and then put the next better grade in it. Last thing you want to do is destroy a friend's borrowed engine from pre-ignition / pinging just to save $0.20 a gallon on fuel. Keep an ear open for pinging especially climbing hills.

At fuel stops, walk around and check tire temperatures. Check for bad smells like brakes heating up.

Climbing hills, shift down into 2nd/Super before the kickdown does it for you. You want to be in 2nd/Super before you loose too much speed. You can do up to 60mph in Super continuously. If the gearing has been modified with a higher ratio Final Drive, then hopefully there's a tachometer, you can go continuously up to 3000 rpm without hurting anything. Maybe even a little higher but I personally don't like to race it for very long at anything over 3500rpm or so, that's just me. Drop it into 1st if you loose speed and get down to 35mph.

Descend hills using a lower gear to engine brake down the hill. If the engine can't hold back the coach in that gear then you need to hit the brakes briefly, but hard, and shift down into the next lower gear so the engine can act as the brake while going down the hill. If you don't do this and instead use the coach brakes to maintain speed while descending, you may end up with no brakes at the bottom of the hill. If there's a town down there, there's usually a stoplight and that's going to be a problem. 40mph in 1st is 3500rpm with the stock 3.07FD, and that's ok for a 12,000lb 40yo automobile based RV to go down a mountain side. Nobody's going to be mad at you for being a little careful coming down a mountain. And if they are, they'll get over it. Better than blowing through the town out of control with no brakes.

Enjoy your trip, but be careful, these are contagious! You'll probably end up owning one after this trip is done

 

[Matt Colie]

Hugo,

Read what Todd wrote again....
He has a very good set of instructions for descending.

Greasing the rear is not that much of a bother. Find out what the owner is using for grease. There should be one in the coach's kit. If not, it would be a good gift. You do this standing up and only about every second or third day if you are normal folks. (Not many will ever do an 1100 mile day.)

Will you be running a GPS? Even if you are, prime the other to be the navigator through urban areas. This can greatly unload the stress on the driver. Mary decided she likes driving Chaumière some years back, so I am usually the navigator these days.

If you have other questions, that is why we are here.

Matt

 

[mrazekan]

Quick question regarding rear ride height. Manual says 11-11/16" +/-1/4" from ground to the top of the slot.

I'm measuring 16" with 58psi in each bag. Do I really need to drop pressure to drop the frame by 4+ inches? How much is too little pressure in the bags?

The auto leveling system is not working and I don't have time to debug the system now. Somone put in shutoff valves that cut the system off. They were closed when I got it. I tried opening them up and running the system and the bags were not airing up even in manual leveling mode.

Thank you in advanced.

Hugo

 

[LarryW]

Quick question regarding rear ride height. Manual says 11-11/16" +/-1/4" from ground to the top of the slot.

I'm measuring 16" with 58psi in each bag. Do I really need to drop pressure to drop the frame by 4+ inches? How much is too little pressure in the bags?

The auto leveling system is not working and I don't have time to debug the system now. Somone put in shutoff valves that cut the system off. They were closed when I got it. I tried opening them up and running the system and the bags were not airing up even in manual leveling mode.

Thank you in advanced.

Hugo

It looks like that is a Sully type system...big bag system, so pressures are quite a bit lower than stock system. When I had a Sully system, I ran about 45lbs or so for specified ride height and that was with a heavy 78' Royale. So don't worry about to little pressure. Just let air out till you have the 11 11/16" height on both sides. Putting it at proper ride height (provided that the front is also at proper height) will improve the handling going down the road.

 

[mrazekan]

It looks like that is a Sully type system...big bag system, so pressures are quite a bit lower than stock system. When I had a Sully system, I ran about 45lbs or so for specified ride height and that was with a heavy 78' Royale. So don't worry about to little pressure. Just let air out till you have the 11 11/16" height on both sides. Putting it at proper ride height (provided that the front is also at proper height) will improve the handling going down the road.

Thanks for the tip LarryW. I'll get to it at the next opportunity.

 

[mrazekan]

Wow that is one very trusting friend to loan you their GMC.

Just be aware they are a 40 yo, 12000 lb FWD automobile. They stop like a 70's car used to stop at best, not great compared to a modern car. Leave plenty of room in front of you and keep your eyes well down the road.

Don't be in a rush, enjoy the trip as much or more than the destination.

Ask the owner about how often to check the oil and where it should be on the dipstick. It may burn a little and that's fine, just make sure to top it off.

Ask the owner about fuel octane and then put the next better grade in it. Last thing you want to do is destroy a friend's borrowed engine from pre-ignition / pinging just to save $0.20 a gallon on fuel. Keep an ear open for pinging especially climbing hills.

At fuel stops, walk around and check tire temperatures. Check for bad smells like brakes heating up.

Climbing hills, shift down into 2nd/Super before the kickdown does it for you. You want to be in 2nd/Super before you loose too much speed. You can do up to 60mph in Super continuously. If the gearing has been modified with a higher ratio Final Drive, then hopefully there's a tachometer, you can go continuously up to 3000 rpm without hurting anything. Maybe even a little higher but I personally don't like to race it for very long at anything over 3500rpm or so, that's just me. Drop it into 1st if you loose speed and get down to 35mph.

Descend hills using a lower gear to engine brake down the hill. If the engine can't hold back the coach in that gear then you need to hit the brakes briefly, but hard, and shift down into the next lower gear so the engine can act as the brake while going down the hill. If you don't do this and instead use the coach brakes to maintain speed while descending, you may end up with no brakes at the bottom of the hill. If there's a town down there, there's usually a stoplight and that's going to be a problem. 40mph in 1st is 3500rpm with the stock 3.07FD, and that's ok for a 12,000lb 40yo automobile based RV to go down a mountain side. Nobody's going to be mad at you for being a little careful coming down a mountain. And if they are, they'll get over it. Better than blowing through the town out of control with no brakes.

Enjoy your trip, but be careful, these are contagious! You'll probably end up owning one after this trip is done

Here we 2:30 PM on the first day of the trip and we've made it 42 miles!!!

Travelling with a 2 year old and a 4 month is an absolute excercize in patience!!!

Thanks for the tips. I've driven big vehicles before. I've driven old vehicles before. I've even driven big old vehicles before, just not on the highway.

The rig likes cruising comfortably at 60 to 65 based on how the engine is sounding. Above that there is a bit more roar and we just are not in a rush. There is a little driftiness to the steering that I hope gets better when I drop the rear end to stock drive height but it's not worrisome.

There was one short climb in those 42 miles. Enough that I shifted to S at 50 and held it there. Verified that the temp sensor is working as it moved just a bit while climbing. The descent was less steep than the ascent so I experimented with D and S and both were able to keep me off the brakes. The speeds and RPMs per gear you provided are very helpful. Thank you.

She is a very cool friend. I think she considers this trip a pre purchase test drive. We'll see.

 

[mrazekan]

Hugo,

Read what Todd wrote again....
He has a very good set of instructions for descending.

Greasing the rear is not that much of a bother. Find out what the owner is using for grease. There should be one in the coach's kit. If not, it would be a good gift. You do this standing up and only about every second or third day if you are normal folks. (Not many will ever do an 1100 mile day.)

Will you be running a GPS? Even if you are, prime the other to be the navigator through urban areas. This can greatly unload the stress on the driver. Mary decided she likes driving Chaumière some years back, so I am usually the navigator these days.

If you have other questions, that is why we are here.

Matt

Thanks Matt. I'm trying to take care of this rig as we are very grateful to our friend for letting us borrow it. So the tips and answers you all have provided have really helped us out. This forum also helped us prepare for the trip. So thank you and all the members.

I bought a grease gun just in case. There's room in her toolbox so it will have a permanent home there. I'll probably wait until I'm in Hood River, OR to grease the back end.

Thank you again and I'll keep this post updated. We're napping the kids at a park now.

Cheers!
Hugo

 

[Matt Colie]

Hugo,

The steering will get better when you let the rear down to ride height. For a fast gage, put a fist between a rear tire and the wheel opening. It usually seems to be about there. It can change a lot with water and fuel load. So be ready to watch it.

Do you have a working air pump with you?

Enjoy the journey.

Matt

 

[mrazekan]

Hugo,

The steering will get better when you let the rear down to ride height. For a fast gage, put a fist between a rear tire and the wheel opening. It usually seems to be about there. It can change a lot with water and fuel load. So be ready to watch it.

Do you have a working air pump with you?

Enjoy the journey.

Matt

Hi Matt,

I used your fist measurement advice and aired the bags down. It drives significantly better. I couldn't find my air pump and was planning on picking one up on the road.

Trip update: We decided to turn around. My first son did not do well in his car seat until he was over a year old. His little brother appears to have inherited this trait. My sister said our babies are broken as all babies sleep in cars. I though it was the lack of fumes due to modern cars being fuel injected but The Whip provided plenty of fumes.

At the mileage we were making per day, it would have taken us 5 to 6 days to make the trip, then another 5 to 6 to come back. The baby could do more than 30min before crying. When we pushed him, the screams were too much unfortunately.

We'll still keep it for a couple weeks. I'll fix a few things and hopefully return it in better condition.

Thank you for the advice. This does not kill the dream as The Whip was doing fine. It's the family that just can't put the miles in.

Pic below of what we spent most of our travel days doing.

Be well.

 

[Matt Colie]

Hugo,

It could be something unrelated. Like maybe the kid is cutting teeth or growing.

We had little kids once (about 40+ years ago). We always traveled at night because I liked it and the kids slept while we drove the 835miles to my parents.

It also could be that s/he is growing. About that long ago, I read this paper that answered a lot of questions.
A growth study was done somewhere in Scandinavia. Every day, at the same time of day, they measured infants. They were expecting a few mm of growth in a day. At the end of the first week, they were doubting there plan. They were not seeing what they expected.
Then BAMM! A kid would grow 5~10mm one day to the next. That was the way it was from then on with one growing 17mm/24hrs. Mother was a wreck, now wonder, with all the stuff that has to stretch for that to happen that kid had to be hurting......
This made me feel better because I had once put my son down for the night in a sleeper, and in the morning it was so small his toes were crammed.

Best of luck with every thing.

Matt

 

[pvfjr]

Sorry the kids didn't cooperate, but they'll come around in time! Mine are 3 and 5 now. When they were 2 and 4, they put up with driving from Phoenix to Salem after we bought our wrecked and non-running GMC at an online insurance auction. It was a very interesting trip home, but it was at least doable. One year sooner would have been impossible. Enjoy the rest of your time with the coach! Getting to borrow one is a very rare opportunity indeed.

 

[kmorefield]

Hey Hugo,
I just saw your forum posting... sorry the trip didn't fully pan out. Where are you guys from? I live in Redding, and was just preparing to warn you about some upcoming bad weather, when I saw that you cut your trip short... I don't have much advice for the very young kids. In a few years, a tv or iPad might come in REALLY handy for traveling - as long as they don't get car sick...