How much oil in an 8V71? (and other questions)

[Barney Five]

I have this Greyhound conversion with the 8V71 engine and I have no clue what transmission except it's automatic. But my question is, how much oil should this behemoth take and how often does it need to be changed? The dipstick seems to be a jury-rigged affair but it looks like it's about an inch down after driving it from San Antonio to West Virginia, about 1400 miles. And it looks pretty black. I don't know whether the oil was changed before I drove it up here. An oil company up here is trying to get me to put in their brand of oil which has an ash value of 1%, whereas I do know the specs on it is .85%. Tejas recommends Chevron Delo 100 but I'm having a dilly of a time finding a source here. Nearest O'Reilly's is over 200 miles so I'm a little reluctant to drive after it. There's a place that will analyze the oil for $25 to see whether it needs changing. I'm new at this game so some experienced commentary would be very welcome. Thanks.

[bevans6]

What actual model/brand of bus is it?  Greyhound ran lots of different kinds of buses.  8V-71 engine wants straight weight SAE 40 oil, CF-2 (now an obsolete rating but the containers still seem to have it on there) with ash content less than 1%.  An 8V-71 usually takes about 7 gallons, although you get different engines being installed over time, and my ex-military engine takes closer to 10 gallons.  The oil level should be 1" below the bottom of the block where the oil pan bolts on, so you can measure up your dipstick and mark it.  Running it a gallon low can stop some oil burning.

Brian

[Barney Five]

It's a GMC 4106. With the pan on and the dipstick at a slant it seems it would be hard to measure an inch down from the block, or am I missing something? Yes, someone suggested it would be "about 7 gallons," but that seems a little imprecise. Are these engines very particular about exact levels? I suppose I could run it and find out, but you're fooling with many bucks there and I hesitate to be that brash.

[Barney Five]

Make that a 1964 GMC 4106.

[luvrbus]

The oil stick should be 26 1/4 inches long from the top of the tube if that part is original if you need the high and low marks let me know I can get those for you put 6 gals and start then see where it is on the stick after about 30 minutes of shutdown

[John316]

Barney,

Welcome aboard. Glad to have you.

Here are a few tips. A good introduction goes a long ways. Maybe even some pics of your bus. There are a lot of good folks on here and someone might even recognize your bus. Also, a pic or two of your engine might help.

The buses are usually tough old birds. If you experiment with your oil levels you shouldn't have any problems (within reason of course). Each setup is usually different, so it isn't real easy to say exactly how many quarts you need. Ours holds 10 gallons.

Cheers,

John

PS, I almost forgot, until our posts crossed. Clifford (luvrbus) is rock solid. If he says something you can go to the bank with it. Listen when he says something.

[akroyaleagle]

Barney,

In most of the old detroits, the oil will be black as soon as the engine is run once.

Use 40wt oil.

I would change it if it was mine just to know.  Measure what you took out, add that amount back.
If the level is the same, add one gallon.
If it's an inch low that's probably about a gallon if it also corresponds with the low mark.
All the 8V71s I have dealt with hold about 7 gallons. You will also verify the dip stick this way.

The distance you drove it is pretty good to only be a gallon low in a bus of that age.
Most will tell you that a gallon per thousand miles is normal. At that rate, every 7000 miles equals a oil change to some folks I know.
I don't think I can argue with that as long as the filter gets changed.

I change oil at 6000 miles. My DD books recommend at 10,000 miles.
My 8V92 doesn't get a gallon low in the 6000 miles. I run it 1/2 gallon low.
I also ran my old 8V71 1/2 gallon low. If I filled it, everytime I stopped it was 1/2 gallon low. Mine don't seem to like to be full.

Always change the filter with the oil.
Go to Detroit Dealer, get a sample kit and follow the instructions. Less than $20 including the analysis.
You will then have the known baseline. You will also be told in the report if there are indicators of impending problems.

Look in the phone book for oil suppliers in your area. Any of them can order oil for you. They will probably beat the auto parts places prices.
Or just tell us where you are and there may be a nut near that can help.

The trans is probably a Alison 740 or similiar. We can adress that in another post. If the bus moves when it is in gear, it's OK.

Hope this helps. Don't hesitate to ask any questions. There is immeasurable experience here.

[RickB]

Welcome to the addiction! Its almost a certainty that you have an Allison 730 transmission in your bus. The oil thing is daunting at first but keep in mind they designed these things to be driven 24/7 and they figured in alot of safeguards to protect the bus and passengers from drivers who tended to overlook routine maintenance. Hence the norm of 7 gallons of oil. Straight 40 wt rotella or delo or try fleet farm for their straight weight oil. Just make sure its specifically for Diesel engines and that its a detergent oil.

Rick

[Barney Five]

Thanks, guys. Lots of good advice! Well, first off, it's a GM, not a GMC like I said first.

luvrbus: Obviously it is not an original dipstick, cause it's 24" long and has "F" with two dots punched in it at 21-1/2" and "L" with two dots at 22-1/2". If you could check those measurements for me, that would be great!

John316: As for an intro, I just got on here and don't really know my way around the site yet. I saw something about an intro when I first got on but I don't remember how to get back there. I'll scare up some pics of the bus and try to find the right place to put them. I was also wondering where I should put a pic for the avatar on the forum. I looked and looked and couldn't see it anywhere. I know it's there somewhere, but each site is different and I just haven't located it yet.

akroyaleagle: Seeing as how this bus is sitting almost on the ground, I am wondering if there's an easy way to drain the oil rather than crawl under and pull the plug. I saw a drill-powered pump somewhere. Could I drop a tube in the fill pipe and suck the oil out with one of those? If so, how long a tube would I need? And if these things are as forgiving as it sounds, how low can it get when the chips are down, and not shell the engine?

BTW, Joe, I spent some of my growing-up years just up the road from you at Redfield. Every summer my church would have camp meeting at the fairgrounds there in Huron. Small world! But we are near Martinsburg, WV, now, in case someone near here can give me a source for the Delo 100 oil. Advance Auto Parts has Delo 400 but it's multigrade.

RickB: I wonder if any of the safeguards extended to the transmission? Some time after I got it I was driving home from a shop when the transmission light started blinking, and it wouldn't pull our steep driveway. Had to get our Grand Caravan out front to help it pull up onto flat ground. Discovered the transmission was TWO GALLONS low. Haven't had it out since I refilled it, but I'm wondering how much permanent damage, if any, that would do to it. It moves ok on flat ground if that is the criterion.

On another part of the bus, my air bags leak down rather quickly, some in a few hours and others in a few days. Can anyone preview what I'm likely to find under there that would leak that bad? I haven't been under it so I don't even know if it is metal or plastic tubing.

Again, guys, thanks for all the help, and if you think of anything I should have asked, I don't mind you answering it beforehand!

Bern

[Dreamscape]

Welcome Barney!

You are getting great advice, and this is the place to get it.

Sounds like you are in for an education, we all started right where you are, so don't feel bashful. You are asking the right questions and will get correct answers.

If you don't have a manual for your bus, get one. Also get manuals for you DD8V71. They come in handy and will give you good reading material during the winter months.

You will need to air your coach up and set blocks under the frame to provide safety. Then you can crawl under and do your work.

Have fun and be safe!

[luvrbus]

From the tip that goes into the pan the stick is 2-1/16 in to the low mark 3-1/2 in to, the full mark from the top 22-5/8 to full 24-3/8 to low it doesn't go into the block like a normal bus but the upper part of the slope housing I guess you could call it the upper pan,the lower pan is the only thing that is straight and normal on the GM's lol  


I have a factory stick and housing here that belongs to Mike (AKA) Red Ryder on this board I am sure he would give it 2 you or make a great deal contact him and I will ship it to you and you pay the freight

good luck

[longjohn]

Welcome to  the nuts world Barney!
As everyone says you will get the best of help and info here , as john said when Mr Clifford  tells you something it is pretty much gospel.  as well as everyone else who offers ideas and help........

[baker4106]

My 1961 4106 takes 7 gallon.

[RickB]

My thought on the transmission is the smell of the fluid will tell you alot about the condition of the transmission. If it smells burnt, sweet and strong that's a sign it got hot. Find a good shop somewhere close get the motor and transmission up to full temp (around 180) and have an experienced mechanic give the transmission dipstick a good smell test. If its bad you'll never need help diagnosing it again. You never forget that awful smell.

Rick

[OneLapper]

Great info Clifford!!

At one point I had three 8v71s on my garage floor, two were out of 4106's and the third a fishbowl.  All three had different length oil dip sticks and tubes!!!

Ditto on the 7 gallons in a 4106.