ndcowboy Posted October 16, 2012 Share Posted October 16, 2012 Here is some background. Dad and I bought this truck this spring for hauling grain and hay for our farming operation. We typicaly put between 5 and 10 thoudand miles a year on a semi. It is a 85 superliner, 350 mack engine, 12 spd mack tranny, 4.17 gears in the rear and the power divider has a air swith in the cab. The hourmeter is around 9700 hrs and odometer is at 45000. So I can assume there is a million something miles on the truck. We have newer grips on the rear axle and 1/4 to 1/2 tread on the front axle. Last week harvesting corn that we deliver 45 miles away I noticed a change in the sound of the truck. Thought maybe i was having tire issues only to discover the top of the rear carrier was too hot to touch with a bare hand and the vent was steaming. I also noticed that the u joint was going out. I was a mile away from an off ramp so i limped it to a parking lot and shut it down. Went back the next day to check oil levels and replace the u joint and noticed that I could rotate the driveshaft. The truck losses air overnight and I reliazed the power divider was locked in and had disengaged. Which means that several trips were made with the divider locked in which in turn made peices of the pinion (Upper) gears in the rear carrier. I removed the side covers on both carriers and the front appears to be fine other than a fair amount of fine metal dust on the magnets. The rear pinion gears are missing all there teeth. I removed the driveshaft inbetween the drivers and locked in the power divider and gently drove the truck home. A rebuilt carrier from Mack costs more than I paid for the truck, Could I get by just replacing the pinion gears. They are a 14 and 17 tooth. This would include new gear lube and flushing the metal out of the rears. Could I flush and replace lube and run the truck to finish harvest using the front to drive the truck with the power divider locked in and fix the rear later. I figure I would have about 6 loads 40 miles one way.Any advice would be appriciated and thanks in advance. Quote Link to comment Share on other sites More sharing options...
smorse54 Posted October 16, 2012 Share Posted October 16, 2012 Unless you have the right tools to rebuild the carrier I wouldn;t mess with it.You can usually get a good uced one from a junk yard or whatever. 4.17 was a very popular ratio and won't be hard to find.Whatever way you go be sure to remove hubs to clean/check or replace brngs and races. If you neglect to it will haunt you. Just my thoughts. Steve Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted October 16, 2012 Share Posted October 16, 2012 should be able to find a good used diff for $500-$1000 depending how hard you look. would also be faster to get it back on the road. The parts for that repair will cost you almost as much as a complete used diff.just my .02 Quote Link to comment Share on other sites More sharing options...
pmolitor Posted October 16, 2012 Share Posted October 16, 2012 Manders diesel in lakeville MN has rebuilt rears for very reasonable prices. Under $1400 if I remember corectly. They are easy to deal with and ship anywhere. Housby in des moines IA rebuild their own. Just dont remember the price. Quote Link to comment Share on other sites More sharing options...
Wayne Gentry Posted October 16, 2012 Share Posted October 16, 2012 (edited) I pulled the rear driveshaft on my B 61, locked the front diff, and drove it from Montana to the west coast. No problem. Should get you thru the season! Just remember that it will act like a tag without a lift! Traction will be poor, so if you are useng it in a field, you may get stuck easy! Edited October 16, 2012 by Wayne Gentry Quote Link to comment Share on other sites More sharing options...
rsb502 Posted October 17, 2012 Share Posted October 17, 2012 Here is some background. Dad and I bought this truck this spring for hauling grain and hay for our farming operation. We typicaly put between 5 and 10 thoudand miles a year on a semi. It is a 85 superliner, 350 mack engine, 12 spd mack tranny, 4.17 gears in the rear and the power divider has a air swith in the cab. The hourmeter is around 9700 hrs and odometer is at 45000. So I can assume there is a million something miles on the truck. We have newer grips on the rear axle and 1/4 to 1/2 tread on the front axle. Last week harvesting corn that we deliver 45 miles away I noticed a change in the sound of the truck. Thought maybe i was having tire issues only to discover the top of the rear carrier was too hot to touch with a bare hand and the vent was steaming. I also noticed that the u joint was going out. I was a mile away from an off ramp so i limped it to a parking lot and shut it down. Went back the next day to check oil levels and replace the u joint and noticed that I could rotate the driveshaft. The truck losses air overnight and I reliazed the power divider was locked in and had disengaged. Which means that several trips were made with the divider locked in which in turn made peices of the pinion (Upper) gears in the rear carrier. I removed the side covers on both carriers and the front appears to be fine other than a fair amount of fine metal dust on the magnets. The rear pinion gears are missing all there teeth. I removed the driveshaft inbetween the drivers and locked in the power divider and gently drove the truck home. A rebuilt carrier from Mack costs more than I paid for the truck, Could I get by just replacing the pinion gears. They are a 14 and 17 tooth. This would include new gear lube and flushing the metal out of the rears. Could I flush and replace lube and run the truck to finish harvest using the front to drive the truck with the power divider locked in and fix the rear later. I figure I would have about 6 loads 40 miles one way.Any advice would be appriciated and thanks in advance.Well new tires on the rear and nearly dead tires on the front with the pwr divider locked in on asphalt aint gud! I would get another rear carrier from a junkyard and give it a shot dont try to rebuild it if you dont have the correct tools it will cost you more in the long run, when you swap the carrier make sure to pull the axles out of the axle and clean the crap out of it to remove metal shavings,chunks,etc. I know its hard to resist the temptaion to just run it as is but pulling a heavy load on the power divider using the front diff is REALLY hard on the power divider and the front axle, and remember there is still metal floating around in the rear until you get it out that will probably kill the bearings if it hasnt already, I would swap them when you get another carrier. On another note if you think its too costly to put a carrier in the truck I may buy it, how much? I hate to think what you paid if a $750 carier is more than the truck is worth. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
theakerstwo Posted October 17, 2012 Share Posted October 17, 2012 Well new tires on the rear and nearly dead tires on the front with the pwr divider locked in on asphalt aint gud! I would get another rear carrier from a junkyard and give it a shot dont try to rebuild it if you dont have the correct tools it will cost you more in the long run, when you swap the carrier make sure to pull the axles out of the axle and clean the crap out of it to remove metal shavings,chunks,etc. I know its hard to resist the temptaion to just run it as is but pulling a heavy load on the power divider using the front diff is REALLY hard on the power divider and the front axle, and remember there is still metal floating around in the rear until you get it out that will probably kill the bearings if it hasnt already, I would swap them when you get another carrier. On another note if you think its too costly to put a carrier in the truck I may buy it, how much? I hate to think what you paid if a $750 carier is more than the truck is worth. Right again Quote glenn akers Link to comment Share on other sites More sharing options...
David Posted October 17, 2012 Share Posted October 17, 2012 Pull one of your axles and note the size and spline count before you start shopping for a carrier. Quote Link to comment Share on other sites More sharing options...
ndcowboy Posted October 17, 2012 Author Share Posted October 17, 2012 Thanks for the replies. Just to clarify when I say a carrier costs more than what we paid for the truck I am refering to a carrier from the local Mack (RDO) dealer. They quoted me $3800 for a carrier and $1300 for a new top gear set. We paid $4000 for the truck and it was full of fuel approx. 250 gallons. I really enjoy the truck. The air ride suspension and air ride cab it a huge step up from a 79 Freightliner cab over. However the 1693 cat pulls like a freight train. I have done some snooping around here and a neighbor has a 83 mack cabover with a set of 3.68 rears. The engine is shot in the cabover and he would sell any parts off the truck for a little better than scrap iron price. Would 3.68 gears be acceptable for farm use? I am worried I would wear out all the gears in the tranny but high gear. Also would it be easier to swap out the entire rear axle assemblies or just the carriers. Both trucks have the same suspension. The cabover also has a dynatard engine brake. I do not. How difficult would it be to install that system in my superliner and would it be worth the effort? As a side note when I first started running the Mack I found the 12 spd tranny to be quite different to drive, however now I find it to be one of the easiest trannys to drive. Quote Link to comment Share on other sites More sharing options...
rsb502 Posted October 18, 2012 Share Posted October 18, 2012 I would grab the 3.68's, if you dont want em I do where are they located and can you get me a price or a phone number? I have 4.64's and need to gear up in a bad way. The 3.68 versus the 4.17 you will loose a little torque multiplication (or power at tthe wheels) but you would only drop about 200 rpm in top gear at speed, the trtxl tranny is an awesome piece of mechanical brilliance it has a gear for every situation and if you treat it right it will last you. The 350 E6 with 4.17's is a good match, you might feel a bit under powered on the highway with the 3.68's but they are good gears for highway speeds it really just depends on your average driving speeds and whether or not you can stand to lose a dab of rear wheel torque. I would think it will pull fine with the higher gears and the 12 speed will keep you in the power band no matter where you run, like I said if you dont want em I do so dont let em go to scrap I will try my best to make a deal on em and get em here for my truck and then I can let someone that needs a set of 4.64's have at my carriers. As for the whole rear swap, I would just swap carriers, those axles have been in there a long time and the crazy thing about bolts that have been tight for a long time is they break and you dont want to deal with that crap on those big suspension bolts the carrier bolts will come out a lot easier, just remember the bolts inside the side cover before you start yanking on the carrier with a front end loader. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
ndcowboy Posted October 18, 2012 Author Share Posted October 18, 2012 (edited) Thanks for all the advice guys. This is becoming my favorite forum it is amazing how much great info is on the web if a person looks in the right place.I am figuring that I will give the 3.68 a try because I will be needing this truck in a big way in about a month to start deliving our stored grain.Superdog, I am located near Bismarck ND and we farm and ranch south of New Salem. The rears are near there. If I am reading your info correct you are in TN. Too bad we aren't closer we could park the trucks side by side in the shop and have a day full of carriers swaps and enjoy a few malted beverages. Slower gears would not bother me because probably 70% of my miles are at 40 mph on gravel roads. I am also content at 65 to 70 on the interstate. With farm plates on our semi we a limited to a 120 mile radius to run without inspections and logbooks.I see Bell Buckle is between Nashville and Chatanooga. I was through there a few years ago with an oversized load delivering an 80k lb. green waste grinder to Atlanta. I scaled out at about 108,000 and found the trip across Mount Eagle to be a new experience for this flatlander.Thanks again everbody and I need to get to work. Also any advice on the dynatard system? Edited October 18, 2012 by ndcowboy Quote Link to comment Share on other sites More sharing options...
b61mack Posted October 19, 2012 Share Posted October 19, 2012 Thanks for the replies. Just to clarify when I say a carrier costs more than what we paid for the truck I am refering to a carrier from the local Mack (RDO) dealer. They quoted me $3800 for a carrier and $1300 for a new top gear set. We paid $4000 for the truck and it was full of fuel approx. 250 gallons. I really enjoy the truck. The air ride suspension and air ride cab it a huge step up from a 79 Freightliner cab over. However the 1693 cat pulls like a freight train. I have done some snooping around here and a neighbor has a 83 mack cabover with a set of 3.68 rears. The engine is shot in the cabover and he would sell any parts off the truck for a little better than scrap iron price. Would 3.68 gears be acceptable for farm use? I am worried I would wear out all the gears in the tranny but high gear. Also would it be easier to swap out the entire rear axle assemblies or just the carriers. Both trucks have the same suspension. The cabover also has a dynatard engine brake. I do not. How difficult would it be to install that system in my superliner and would it be worth the effort? As a side note when I first started running the Mack I found the 12 spd tranny to be quite different to drive, however now I find it to be one of the easiest trannys to drive. Are you sure they are not 3.86, in the early 70s they had 3.86, in the mid 70s they had 3.87s then went back to 3.86 in the 90s i have a set of 3.65, never heard of 3.68. Ron Quote Link to comment Share on other sites More sharing options...
rsb502 Posted October 19, 2012 Share Posted October 19, 2012 I actually missed that 3.68/3.86 gear thing, I had 3.86 in my old CH and I dont think I have ever seen a 3.68 either, Cowboy that hill they call Mt. Eagle will surprise ya its steep and curvy so its hard to get a run at the good parts, thats why I like my E9's they seem to take that 7% grade down to about 2%. I would love to have some 3.86 rears for mine I will keep looking and they will be great in your truck for your use they are about as high as I would go with the 12 spd you will have plenty of gears to choose from to keep that 350 around 1500 where they like to pull. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
ndcowboy Posted October 19, 2012 Author Share Posted October 19, 2012 you guys caught me in a dyslexic moment on the gear ratio. I don't thing I would like to try Mt. Eagle with my old 350 at 100,000 pounds. I know it could do it but my patience couldn't. I was running my companies 379 Pete with a 475 cat and 18 spd.Thanks again guys. What type of use does your truck see Superdog? Also I would like to post some pics. How do I attempt that? Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted October 19, 2012 Share Posted October 19, 2012 3.87 rears and a 12 speed is a great combo. As said you will louse a little power but you have every gear you need to work in the field or get home fast on the hi way Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted October 19, 2012 Share Posted October 19, 2012 Regarding the engine brake.... Some worked better than others. From my experience the jake worked better than the dynatard. But both were weak. They barely slowed the trucks I drove... Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted October 19, 2012 Share Posted October 19, 2012 What type of use does your truck see Superdog? Also I would like to post some pics. How do I attempt that?Click more reply options and you will see a place to attach files. Select your pic off your computer then click upload... Quote Link to comment Share on other sites More sharing options...
rsb502 Posted October 20, 2012 Share Posted October 20, 2012 I just take this one to truck shows, my 84 I pulled containers, dump trailers and lowboy the 84 had E9 440hp 12spd and 4.42 rears it would pull anything you put behind it. I have an 85 now with an E9 450hp, 9 spd and 4.64 rears (till I can change em to 3.86) I am just taking this one to shows for now I work for the railroad now so no truckin for me anymore. I had a 93ch with an E7 400 9spd and 3.86 rears, 04 granite asshole ai427, 310m 10spd and 4.64 rears, ok I'm tired more for later. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
rsb502 Posted October 20, 2012 Share Posted October 20, 2012 Ha,wtf man, I typed aset or tried to and my phone decided I meant asshole my phones a jerk. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
slpwlker Posted October 20, 2012 Share Posted October 20, 2012 ehh worse things have happened Quote Link to comment Share on other sites More sharing options...
ndcowboy Posted October 23, 2012 Author Share Posted October 23, 2012 I found a 4.17 rear carrier in the neighbor's bone pile that was in a wrecked truck. Only hang up is the case has no mounting holes for the drag links bracket. I think these could be easily drilled and tapped. I should say easier than swapping internals.I am also attaching pics of our two big trucks. 1 Quote Link to comment Share on other sites More sharing options...
rsb502 Posted October 25, 2012 Share Posted October 25, 2012 Which link? The torque rod from the frame to the axle going across from side to side? That bracket bolts to the back of the chunk and I have never seen a carrier that didn't have the holes for it. The other torque rod from the top of the carrier forward to the trunnion has two different mounting styles one is saddle mount with two bolts on the carrier the other is taper mount with one nut it works like a tie rod end. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment Share on other sites More sharing options...
ndcowboy Posted October 25, 2012 Author Share Posted October 25, 2012 It would be the side to side rod mount. Both have the single bolt (ball joint style) on the carrier. The bracket bolts to the chunk using four 3/4" fine thread studs in the rear face. The carrier I am looking at has the mounting face but no holes. It is out of a 70's cabover with no sleeper with a grain body and hendrickson spring suspension. The neighbor replaced both rears and suspension in that truck from an early 80's cabover he wrecked because he kept wrecking brake cans from them hitting the frame pulling out of feilds with a load. I will try to get some pics soon. Too many other distractions trying to get falls work completed before winter shows up. Quote Link to comment Share on other sites More sharing options...
ndcowboy Posted December 1, 2012 Author Share Posted December 1, 2012 After talking to Lucken truck parts in Winger MN I ordered used pinion gears from them for $350. My bearings and bull gear and the small gear above the bull appear to be good. The pinion gears were pretty easy to remove. Waiting for parts to arrive to reassemble. Quote Link to comment Share on other sites More sharing options...
David Posted December 1, 2012 Share Posted December 1, 2012 Find a fish scale, a twenty ton press and some shim stock while your waiting. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.