Son was driving the 53' 1/2 ton Chev. yesterday, said about 55, and it sounded like the driveshaft broke and started dragging the ground. The motor is rebuilt and so is the transmission. It is a stock enclosed driveshaft and stock rear end. I started it up, put it in gear and it just sat there - went back and I could hear the drive shaft turning in the tube. Whether the shaft is broken, gear stripped, or rearend gears stripped, I do not know. Son said it made a hell of a noise before it coasted to a stop. Suggestions please. Also, on this site, Nate has listed a place to get differential gears @ a higher ratio for higher speed road (versus load) driving. If you put in these gears, is the enclosed drive shaft still rated for 55mph? Will the higher speed gears improve mpg? Thanks much. Kentc
Sorry to hear about the problems. Sounds like something gave way big time. I know the driveshaft joint is not uncommon to grenade. It would be towards the transmission end though, and I would expect you would hear a ton of noise there. May need to do some minimal disassembly for inspection. As for the driveshaft, with the 3.55 gears, it will actually turn slower at the same speeds, so should be good. The company Nate talked about would be Patrick's. www.patricksantiquecars.com You should be able to find them on the net. Good luck....Mike
Kent, I would check to see if it's the universal joint. That's the easiest accessible place to start. Slide the bell cover back on the torque tube and inspect it. If that's ok, then proceed down the line. The gears that Nate was referring to are 3.55 to 1 ratio available through several vendors (who all get them from Patrick's). Going from your stock 4.11 to 1 ratio rear end to a 3.55 will improve your mileage some, but most importantly, it allows you to go faster without overtaxing your engine.
Gears CP has the 3:11 rings also. I believe the price is about the same. Good luck with that~ I know it's a bummer to have to be sidelined from driving!
Sorry about KentC's dilemma. I was wondering how hard is it to install and setup a new set of gears. Pat's sell a kit that costs almost as much as the gears. I'd like to upgrade to 3:55 myself but I'd have to do it myself as I don't trust anyone locally. Is it as difficult as the rearend overhaul manual makes it look?
Rear end I pulled the pan off the back of the differential. Looks like all but the biggest gear is either broken or bunged up. The pinion gear shaft broke in two pieces and I think caused the rest, and not vice versa. Any other comments? kentc
Kent, don't take this the wrong way, but have you considered going with a late model rear end? If you're not concerned about "authenicity", then maybe a F*rd 9" rear end might be the route to go. Those are very compatible with these truck and you can get a 3 something ratio to boot.
Kent's Rear End You know I hadda phrase it like that ! Anyways , you're going to have to _completely_ disassemble the rear axle and Torque Tube to get _all_ the metal chips out of it else all your repairs will be undone in a few thousand miles ~ it must be hospital clean when it goes back to-gether , might be easier to get a good used one from a Hot Rod takeout (they're cheap) and install the 3.55 gear set into that . You'll be wanting to install a new Oakie Bushing up in the nose of the tube at the sale time . It's a buncha work , maybe you'll find an old timer or technical school that'll do it cheaply or free if you supply the parts.... The Torque Tube will easily handle the increased speeds of the truck , as mentioned the gears , shafts , bearings and etc. all are turning _slower_ with the high speed gears in it .
Nate, that was a lob, unfair! Kent's rear end, indeed! OK, hypothetically speaking! You pull the back cover off! You see broken, ground down parts. Now what? Where do you start? Do you pull the axles out and inspect them first? Do you look at the actual gears? There are so many little things that could be affected. Time for a tutorial. Given what Kent said, give us a step by step technique to troubleshoot, if it happened to you! Be precise, because we all are going to print this and probably put it under our pillows tonight.
Yarg It's been like 25 YEARS since I did one . In the middle of the spider gears is a big square block with a flat headed slotted screw ~ remove the screws and rotate the Crownwheel carrier (that's for Neil, us Yanks will turn the Pinion Carrier) untill the pin slides out of the block allowing the spider gears and block to come out . Push axles in 1/4" and the 'C' clip retainers will drop out , allowing you to withdraw the axles completely . Go to back of tranny and split the U-joint , inspect for wear/damage , grab the _rear_ yoke and see if it has any play up or down ~ it does (you knew it would) ? the Oakie Bushing is worn out , time to line up a new bushing and the special tool to remove the old one . you'll need a brass drift or better yet the oldest , hardest piece of hardwood you can find to install the new Oakie Bushing . and a BFH and I mean a B. F. H. . Back to rear end , on each side of the ring gear assy. is a BIG cast pinion bearing holder , you must take a punch and make marks on one side so later on when you re-assemble it , you'll know not only wich side is which but which end is up . remove both bearing holders and use a Pinion Pry Bar to lever the ring gear and holder , bearings etc. out ~ they may pop and land in your lap . Undo the bolts holding the Torque Tube to the pumpkin's snout , have fun wriggling it loose , then loosen the bolts with locknuts on them to release the pinion bearings . I seem to have forgotten how to unbolt the driveshaft proper from the pinion , once you've done that use a brass or lead hammer (NOT STEEL !) to drive the ruined pinion out to the _rear_ There's some very delicate shims on the pinion so don't loose or damage them , you'll need 'em for the new gears . Having fun yet ? I didn't think so and it only gets worse . Use a few cases of de-greaser and long handled brushed and clean rags soaked in de-greaser then poked down the axle tubes like you're cleaning a big old cannon ~ then flush with water and shove white paper towels though , still some shiny stuff on there isn't it ? O.K. clean out all the water and do it again untill the clean white paper towel can be shoved through any part of the Banjo housing and come out clean enough to wipe your mouth with , then you're ready to spray oil in all the nooks & crannies s it won't rust up before you button it back up . (WD-40 is crap in a can , NOT OIL !) ANY bits of metal left behind will rapidly get into your bearings and the new gears and chew them to noisy junk in a few thousand miles ~ guess how I know this ? . Somewhere in here you'll either get revved up and not need me further or decide to take the easy way out and go buy a $25.00 used Torqe Tube and have the new gears put into that but the axle housing (" Banjo ") will still need to be cleaned , sometimes you can find a '51 and newer rear axle complet and upgrade to Bendix brakes at the same time . I hope that hold you for now...
Thanks, Nate! Excellent write-up, as usual! BTW, I was going to send you a case of WD-40 for Christmas, but for some reason, I don't think it would be well-received
differential Ken - When you speak of a Ford rear end, how would the driveshaft work, have one made? What year models would fit and is it an exact fit and/or what modifications are required? What are the differences? I assume you are thinking of a used one. Thank you. Also where might I find a used original one? I wonder if the same fate would not be to this one too. Kent
Kent, check this link for possible donor rear ends http://50chevy.freeservers.com/Suspension_Widths.html#REAR They should be plentiful in the local boneyards.
Rear end Buying a different rear end, what about the drive shaft? Will the u-joints fit, and is the driveshaft cut, refit and welded to length? Thank you. kentc
Torque Tube To Open Driveline What you have to do Kent ; Is find a truck with a tranny that has an open driveline and use it or the back cover and yoke (if you have an Muncie SM420 4 speed) to convert your truck to open driveshaft . The newer rear end will have to have the spring perches fabricated as they're different . You can use many different rear ends as long as the width between the brake backing plates is close to the same , this avoids the tires from rubbing either the frame rails or the fender lips . Late 50's vintage GM pickup rear endsfit great and often come with desireable 3.90 ratio gears . most any donor rear end from an automatic equipped vehicle will usually have a ratio that'll work well with your original engine and tranny . I hope this helps .
The law in Tennessee and maybe all over is that you can shorten one by cutting the end off, shortening the shaft and putting the end back on. However, if you have to lengthen one, you have to cut both ends off and put a new shaft all the way. You cannot have more than 2 welds, one at each end. I would take some measurements of the original play in the telescoping part of the shaft then take into consideration how much longer or shorter the new one has to be and reproduce that amount of play in the new setup. Usually you can find a shop that will make up your new shaft but, unless you can take the whole truck to them, you will have to tell them what length you want. I lengthened my drive shaft and it cost about $100 including the all important balancing. Gater
If it is a torque tube type and you want to drive to the Dallas area I have several left over from conversion jobs. Help yourself to one, gratis, if you want. Nate forgot to say you will need two rolls of towels, one to clean the rear and the other to try and get the foulest smelling lube known to man off your body--especially if it's been cooked. Have you ever seen the comic that has guys standing around a hand washing station that has a sign saying "Employees Must Wash Hands Before Returning To Work" and on the wall is the companies name, "Acme Manure Bagging Co."? Your hands won't be qualified to touch s--t after being in this stuff.
Dude, Drive down to Evan and take him up on his offer of a free rear end. You will need a trailer for sure, but it is the easiest bolt up fix for your problem. Andy