dak49

I have had experience with both the Jake and exhaust brake, I think they are pretty close as far as slowing the truck, but the Jake does do a little better job than the exhaust brake. I do think the jake is better because of less wear and tear on the engine. What a Jake does is open the exhaust valve at the time the piston is coming up on the compression stroke allowing the compression to go out the exhaust thus giving the added noise in the exhaust. The exhaust brake will do somewhat the same thing, with a little less noise, and less retarding effect. And less cost. If I could get a jake that's what I would prefer, but the choice is yours. Good Luck Dak49

Bob, I just reread your original post and seen that you are going to use a 6 speed, I would think with the 5:02's it wouldn't be a problem on take off, but if the Volvo is slow, then I'm guessing the Mack would be as well. I think the 6 speed would have a low enough lo gear to get it started pretty fast, but with 70,000 pounds it could be kind of slow. I wish I could be of more help sir. Good Luck and keep us posted as to how everything works out. DaK49

Good Grief, where do people come from?? He is right the Mack rears are dual reduction, but 5:02 is 5:02 not 5:37. anyway after I did the math it works out to about 1875RPM at 45 MPH. Again, that's assuming a direct drive transmission. Do you have any idea how many gears the trans will have? That will make a big difference as well. For example, if its a 6 speed direct it should have plenty of low end power, if it has 4 speeds, it could be another dog, no pun intended. It sounds to me like the dealer is trying to sell what he would want and not what you need, or want. One last thing, if it won't run much faster than 45, I would think resale wouldn't be very high either though, unless someone just wanted it for off road use. Good Luck, and keep us posted as to what you wind up doing. Dak49

Bobc, welcome to BMT. I just did the math and with 6:06 gears the engine would have to turn about 2290RPM @45 That's using a low-pro 22.5 tire and a direct drive transmission. If you have an over drive trans then it would be closer to 1695RPM. That would be with a .74 overdrive trans. You would really need to know the correct tire size (RPM =rev's per mile) most tire manufactures can give you that info. I was using a 504 tire RPM (for a low pro 22.5) A bigger tire will have a lower tire RPM and a smaller tire would be higher. The way to figure it is like this: take the speed that you want to run (cruise) in this case I used 45 then multiply that times the trans high gear ratio if its an over drive, if not use 1 (or just skip that one) then times that by the rear ratio times tire RPM. Then devide by 60 Example 45x1x6.06x504=137440.8 devide that by 60=2290.68 engine RPM. speed x trans top gear ratio x tire RPM = devide by 60= engine rpm @ indacated speed I hope that helps you and maybe a few others, let us know what you decide to go with. Dak49 P.S. a direct drive trans has a 1to1 ratio that is why if you use the gear ratio you would need to use 1.

I like the 60's and 70's as the first truck I ever drove on highway was a 1966 R model, it had the 237, and quadraplex transmission, then moved up to a "77 "R" with the 285 horse and 2 stick 6, I really like the 285 and the 2 stick 6. Then I move to a Frieghtliner and I felt like it was a couple of steps backwards. I did get a chance to drive a new '97 CH and I liked it as well, but I think the "R" just looked tough, and I just like it more. Dak49

That Volvo suspension is the same as the European Volvo's. I was in Iraq working as a truck driver and we had some of the cabovers. I didn't like them because Volvo did some really dumb things, like the transmisson didn't have any support to help keep it in place. The result was broken clutch housings, (if we were lucky) or the trans would fall completely out. We also used some Mercedes, they weren't much better, they hard lined the air line from the engine to the frame, just about every 3000 km's the air line from the compressor to the frame would crack. The machanics made some rubber mounts where it met the frame to help absorb the vibration that helped a lot. I think a better solution would have been to use a flexible hose to begin with. Ok I guess I over stayed my welcome this time. Good Day all, Dak49

It looks correct to me, the plug should be hour glass shaped and the part that goes inside is tappered so it can be started in the plastic lens easily. One thing though, there should be a vent hole (very small) in the center of the plug so as the oil gets hot it can expand without blowing the plug out. Good Luck Dak49

I think you could actually get a little better fuel mileage from a 10 or 12 speed by shifting earlier and keeping the engine in the high torque rpm range. I think that's what Mack did with the "Econodyn" engine, they cut the rpm back to 1800 then used a 9 speed or more gears to help keep the engine rpm closer to 1200-1300. One of the problems though was Mack didn't have any real high speed rear gears to get your speed back, hence the overdrive transmissions. I could be wrong about my info, but I'm pretty sure I am close to correct. Have a good day Dak49

If I understand the question correctly, I think what Redman is talking about is when he makes a range shift from low to high. I have had the same problem before with the Fuller 13 speed as well, what can cause it is from shifting at too high a speed from high range to low range. I think there is a note on the shift pattern indicator that you are supposed to be below 25 MPH before shifting into low range. That doesn't help, but could explain what may have happened. Good Luck Dak49

Hello everyone, I just got the VIN number FS785LT 20415, that's on the door, there is another on the door jamb FS 785LT (#missing)3263. I couldn't make out the missing number. Maybe the door was changed out at some point. Rob you can call me at 479-633-8387 My name is Bert, I can get you in touch with the guy that own's it. It is still hooked to a trailer, and I noticed on the driver side it has 2 flats on the drive axle. Maybe they could be aired up, and the air tanks have a valve that could be used to air up the air system. You wouldn't be buying out from anyone, I put it on here so if someone wanted it they could hopefully save it from the scrap yard. If anyone has any questions I'll try to answer them, or get you the owners phone number so you can call him. I just would rather see it go to a home rather than the other alturnitive. Good Day Dak49

I remember Chief as well, if I remember correctly they went out in 1978 or 79. I don't know if the trailer is for sale or not though. Good Day Dak49

Welcome Underdog, that is a very good looking truck and trailer you've got there. I'm new to this site as well, and I've only seen good people and good humor. Dak49

Other Dog, I agree its in pretty good shape, I just can't afford it right now. I'm thinking, I may try to borrow the money just to save it from being "scraped". One problem it does have is someone cut about a 5 inch hole in the top just above the center of the cab and rain, snow, and ice tore the head liner down and the fiber glass is all over everything. I do think a good clean up and a little work it may run, and look a little better. It does have a lot of surface rust, and some was pretty deep, but mostly from what I could see its just surface. I'll try to get the serial number this wekend and post it to see if anyone can figure out just what it is. I remember seeing it was built in California, but that's all I can remember. I have some more pictures, but I kept getting "photo is too big" Thanks Dak49

I tried to up load a photo but I must have done something wrong, sorry guys maybe when I figure it out I'll be able to get on here, if you look where I joined there are a couple of pic's of it there.

Here is a picture of an F model I found in Arkansas, I'm not sure what year it is, its a FS700L it has a Mack 6 I think its a 300 and a 5speed trans. has something other than a Mack drive axle. It is for sale, the guy told me it hasn't been run for about 8 years, and it is kind of rough. He said it ran good but had some electrical problems when he parked it. He wants $700-800 for it. He thinks he would get that much out of it from the local scrap yard. It only has a single drive axle.

Here is a picture of an F model I found in Arkansas, I'm not sure what year it is, its a FS700L it has a Mack 6 I think its a 300 and a 5speed trans. has something other than a Mack drive axle. It is for sale, the guy told me it hasn't been run for about 8 years, and it is kind of rough. He said it ran good but had some electrical problems when he parked it. He wants $700-800 for it. He thinks he would get that much out of it from the local scrap yard. It only has a single drive axle.

Hello all, I go by dak49 I have visited this a few times, I do not own any truck, but I have driven for just over 30 years. I started out in a 1966 R model with a 237 and Quadraplex it wasn't fast but it interesting in that since it was a Maxidine engine I could shift just about when ever I wanted. I later moved up to an R model that had a 285 horse and 2 stick 6, I really liked that. Then I started driving a Freightliner, it was ok, but I think after driving a Mack it was a let down especially with a Detroit, 8V71. If anyone is intrested, I found an FS700L for sale, its kind of ruff, and its only a single drive axle, I think its a 300 horse, with a 5 speed, well the 5 speed I know for sure. Hasn't run in about 8 years, some rust but the floor seems solid. Its located in Rogers, Arkansas. I talked to the guy that owns it and he said he would take $700-800 for it. I'll try to post some pictures of it here. (if I can figure it out)