rear end id
New User
Joined: Jun 1999
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rear end id
The guy i bought my truck from says the rear end was changed to a 9'' 31 spline rear.How can I find out if it is a 9'' rear? Also I'm opening the hogs head to find out exactly what gear ratio I have so can I count the splines from there?I am geared to high so I need to know exactly what I have so I'll know what to buy.
Senior User
Joined: Jun 1999
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rear end id
Well, the 9" is easy to tell once you know 2 things.
1)The rear cover (what you see when looking at the rear end from the back bumper of the truck) is welded in place, and is NOT removeable.
2) The 9" has what is called a "drop out". There are bolts around the FRONT of the rear end, that hold the drop out to the axle housing. To remove it all you do is pull out the axles (4 bolts on each side) and pull out this drop out.
And your truck will almost definetly be a 5 bolt pattern at the wheels.
Umm, to get the gear ratio (usually the tooth count is stamped on the ring gear) you divide the ring gear by the pinion.
So, 10 tooth pinion, 35 tooth ring gear= 3.50 ratio.
need anything else? post back and I'll be glad to try and help.
Matt
1)The rear cover (what you see when looking at the rear end from the back bumper of the truck) is welded in place, and is NOT removeable.
2) The 9" has what is called a "drop out". There are bolts around the FRONT of the rear end, that hold the drop out to the axle housing. To remove it all you do is pull out the axles (4 bolts on each side) and pull out this drop out.
And your truck will almost definetly be a 5 bolt pattern at the wheels.
Umm, to get the gear ratio (usually the tooth count is stamped on the ring gear) you divide the ring gear by the pinion.
So, 10 tooth pinion, 35 tooth ring gear= 3.50 ratio.
need anything else? post back and I'll be glad to try and help.
Matt
Junior User
Joined: Jul 1999
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rear end id
Thanks for the info.This may be a dumb questio but I know nothing on this subject.Where are the splines and do you just count them or is there a formala to see how many splines are there.Do you have to even know the spline count to change gears?
Senior User
Joined: Jun 1999
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rear end id
He's correct that it's the amount of grooves cut into the end of the axleshaft(where it goes into the differential). Just count them.
However, I have yet to see a 28-spline 9". My old rear end was 31spline, and the new rear end I put in was also 31spline.
You really don't have to care about the spline count when ordering GEARS. But if you buy a locker or a limited slip unit to put in at the same time, then YES you have to know how many splines you have.
However, I have yet to see a 28-spline 9". My old rear end was 31spline, and the new rear end I put in was also 31spline.
You really don't have to care about the spline count when ordering GEARS. But if you buy a locker or a limited slip unit to put in at the same time, then YES you have to know how many splines you have.
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Junior User
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rear end id
Will I need anything other than the ring, pinion, gear oil, and gasket maker to change the gears? Thanks for the info, It saves me time and trouble if I dont have to know the spline count to order the gears.
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Senior User
Joined: Jun 1999
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rear end id
>Will I need anything other than the
>ring, pinion, gear oil, and gasket
>maker to change the gears? Thanks
>for the info, It saves me
>time and trouble if I dont
>have to know the spline count
>to order the gears.
Well, if you haven't a clue how to do it, you might want to consider taking the drop out to a professional.
Otherwise, you might want to consider buying a new gasket for the drop out also. $10 at most, and it usually makes it easier usually to get a drip-free seal usually.
Matt
>ring, pinion, gear oil, and gasket
>maker to change the gears? Thanks
>for the info, It saves me
>time and trouble if I dont
>have to know the spline count
>to order the gears.
Well, if you haven't a clue how to do it, you might want to consider taking the drop out to a professional.
Otherwise, you might want to consider buying a new gasket for the drop out also. $10 at most, and it usually makes it easier usually to get a drip-free seal usually.
Matt
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
rear end id
Chris it is all pretty simple. The rear center in this area it is called a hogshead, drops out in one piece. Just pull the axles, drop the driveshaft (if you have an automatic tie up the end)
You need 3 qt. rear oil, a gasket, and axle seals (opional). I didn't change mine, could be a mistake, I don't know yet.
You need 3 qt. rear oil, a gasket, and axle seals (opional). I didn't change mine, could be a mistake, I don't know yet.
Junior User
Joined: Jul 1999
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rear end id
Last question, has anyone ever heard that you have to set the backlash after installing new gears? Ive just heard this and was wondering if its something i could do or will i have to take to someone else?
Senior User
Joined: Jun 1999
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rear end id
That's why i said you may want to take it to a professional.
Some people say you can get away just fine by marking the adjusting rings, the caps, and making sure what shim goes where,and put it all together and it should be fine. I however, don't believe this.. Unless you have a dial indactor, I'd say get the gears in it, ands take it to a professional..Usually they'll set backlash in a removed drop out for like $50.
Matt
Some people say you can get away just fine by marking the adjusting rings, the caps, and making sure what shim goes where,and put it all together and it should be fine. I however, don't believe this.. Unless you have a dial indactor, I'd say get the gears in it, ands take it to a professional..Usually they'll set backlash in a removed drop out for like $50.
Matt
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
rear end id
Have a couple cans of carb cleaner. While the chunk is out mop the area with a rag, and spray it down with the carb cleaner, mop it again and again until it bees clean. Usually a couple three times will do it.
John
John