I got a rear from a 72 Chevelle that I'm going to put into my 50 Chevy. It was easier than trying to fina a ring and pinion along with the correct carrier for the S-10 rear that I already have. One of the preventative measures that I want to take is to replace the pinion seal now before I put it in the car and find out it leaks. I pulled the nut off the pinion (needed a impact) but now I can't get the yoke off. Do I need a puller to get it off? I assume it is keyed on to the pinion? Any advice would be great. Thanks, Todd
not keyed. A puller will be best, although you can beat it off if you really need to-this can often damage the flange however. Make sure to put sealant on the splines before reassembling and tighten the nut until there is about 6-10in/lb drag on the bearings. Actually this is for the pinion bearings only. I think you need about 30in/lb drag for the rear complete without the brakes dragging.
You do not need a puller. The pinion should side off with a little persuasion of a soft Hammer. It will be splined. Beware that when you break the pinion nut loose you are messing with the pre-load on the pinion bearings. I personally would not mess with it until it leaks or you can get an experienced person to walk you through it.
I am aware of the preload on the bearings. I was told that if you count the number of exposed threads on the threaded portion of the pinion shaft and have a witness mark on the pinion and pinion nut (which I did do) and put it back together the same way you will not mess with the preload. I hope this is true. Todd
What Quad Quad said about the drag is partially correct but that can only be measured when the ring gear is out of the case and with an INCH POUND torque wrench. so usless you are planning to disassmble it completly stay away from this til nessecary or you have a experienced person on hand. I have repalced many of these gears becauxe the yoke was not installed properly.
You also will damage the locking feature of the nut so you will need to install a new nut or stake it with a punch. The thread deal might be a rule of the thumb but you have still released the tension on the crush sleeve. you are going to have to get a feel of how the whole assembly feels before you take it loose. then it is going to take a lot more than 30 inch pounds to get the nut tight enough. That is a measurement of the turning resistance not the torque on the nut.
So basically I should not mess with this at all. I should wait and see if it leaks and deal with it then?? With the help of someone with experience doing this?? Todd
I think you get the message right Tug. Paulweldit mentions the crush sleeve. If you don't know,it is a metal sleeve that goes on the pinion shaft before the yoke and is designed to crush at a certain designed pressure and put a pre-load on the pinion bearing. Once used it must not be reused but must be replaced with a new "uncrushed" one to get the proper load on the bearing.
If there is no up and down play in the yoke before you removed the nut, then it still had at least some preload. Since you took the nut off, I'd replace the seal. I use a small heavy duty puller made for steering wheels. Clean the threads and nut with brake cleaner several times, then use locktite. Run the nut back in gradually with short hits on the impact gun while feeling for the start of drag on the bearings. This is how it was done in shops for eons. If it showed signs of looseness and the resulting oil leaks before you took the nut off, that usually means there was no pressure on the crush sleeve. Then the crush sleeve wears a bit, making it too short to get adequate torque on the nut without over-pre loading the bearing. A cheap fix is a spare thin shim placed between the front bearing and the crush sleeve. Some places still do that rather than fighting trying to "crush" a new crush sleeve...which usually is a bitch in the backyard.
Actually the crush sleeve is what keeps torque on the nut. It crushes at extreme pressure and when it crushes the required amount to get the bearing preload, then there is still a lot of torque still present on the nut. Pre load can be obtained without a crush sleeve, but then there is no way to keep the nut tight Before crush sleeves came about, preload was set with a spacer and shims between the two bearings...then the nut can be fully tightened against that "stack" of parts. If a pinion yoke is run loose for a while, the sleeve usually is worn from rocking around. then the book says replace the sleeve...but you can get by with adding shims at the sleeve to be able to get the torque on the nut and not over tightening the bearings.. ..loose yokes are a good reason to pass on a donor rear. The loose yoke allows the pinion to walk away from the ring gear due to loose bearings, and the resulting wear on the teeth will most always have caused permanent gear whine.
Well the yoke on this rear end is tight (no play or slop). So I guess thats a good thing!! Thanks for all the great info!! Todd
did you ever find out what ratio you had in your rearend ? how wide is the chevelle rear(62 i believe?
ok you did witness mark it then you will have no problem with the preload. just line the marks back up. don't use the impact. i have done it many times. now for a nice tool to make up. get a flat pice of steel. big enough so you can drill 4 holes to fit where the u joint bolts go. then drill a hole in the center for the socket for the pinion nut. weld a handle on between 2' to 3' long. it works. i have them for 9",12 bolt, dana 60 and some others.
If you marked the nut and pinion before you took it apart, you are in ok shape. You will need to put it back to that spot then a 'little' more. This can be a little tricky, as you need to be careful not to go too tight. I may not have the numbers exact, but there is an equation for how much drag (in inch pounds) there should be with the carrier bearings installed as well as the axle bearings. I seem to remember the later GM front diffs on the 4wd/Awd trucks being about this (30 in/lbs). It is how you adjust the amount of side load/preload on the carrier bearings. ANd to be technical, you should use a 'Torque-meter' to measure the resistance. A click type wrench is no good here, but a beam type will do the job. If you think you need to replace the crush collar everytime you take the pinion nut off, you haven't spent much time in a shop that does too many pinion seals. Not to mention that I can't remember the last time I replaced the nut unless it was severly rusted as on a rear sitting outside for too long. They make locktite for a reason. Usually blue is fine for most all of the rearend stuff. F&J has it all down pretty well there, but if you are not too familiar with how much drag you need, the impact gun can be difficult. I would run it down until you get to your marks, then use a ratchet/bar etc to make the final adjustment. But what do I know? Not like I've done this before a few times...
The Chevelle rear is 61" drum to drum outside. It will fit no problem, since I am running stock rims and narrow tires. Once I pull the old rear I'm going to pull the cover and count the teeth on the ring and pinion and find out what I really have. Todd
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