A Leaky Rear

[cjbronco]

I have an 82' with the stock 9" rear. I dropped my driveshaft out a few month ago and had it rebuilt. ever since, my rear leaks after everytime i drive even justa few feet. The seal and gasket are brand new. I think it my by a hairline crakc but still cant tell. Is it time to replace the rea? If so will a rear from an 85' or 86' fit exactly? Also, i know i would have to replace the bearings and brakes and all, but what are the stock gears in the 82 & 86? I have a 4" lift and 33" tires, should i keep the same gearing or move up a little bit? I have to maintain gas mileage.

 

[Wliebhard]

Leaking from where? If you have an auto tranny, they should be 3.50 or 3.55. If the tag is still on it, you can cross reference the build number. I'm sure some one on this forum knows what the build code corresponds to.

 

[jfrbronco]

get the code off the tag and go to broncodata.com and theres a chart to tell you whats in there-

jfr

 

[Broncoholics]

Did you replace the yoke seal or the housing 3rd member seal? If you dropped a driveline you probably damaged the yoke seal when that driveline was bouncing around. Also look and feel the outside of the yoke when you pull it out and see if there are any metal burrs or a ground down area that might damage the seal.

You should be OK with the stuff you have. No need to repalce everyting. Unless the pinion is bent from the driveline banging around...

 

[Justshootme84]

I agree with Broncoholics, you should not need to replace the entire rearend!!! If the leak is near the driveshaft yoke, you may have cracked the housing. It's very simple to swap another carrier unit in place of your stock one. There should be a tag on one of the bolts holding the carrier in that gives a gear ratio, either 3.08, 3.55,3.73 or 4.10. You should get a 4.10:1 ratio for 33" tires, front and rear axles must be the same. The Ford 9" rear axle is worth fixxing and keeping in the Bronco!!

 

[cjbronco]

So, I have to use the same gearing up front in the dana 44? Well 4.11 would be great but i need to think of fuel economy as well. The problem with my leak is that i cant see where its leaking from. Just every morning it leaks from the bottom of the housing.

 

[Desert Donk]

So, I have to use the same gearing up front in the dana 44? Well 4.11 would be great but i need to think of fuel economy as well. The problem with my leak is that i cant see where its leaking from. Just every morning it leaks from the bottom of the housing.

I am having the same problem on my 85. I am going to pressure wash the area in hopes that it will help me to see where it is coming from. Currently I tend to suspect the rear access plate because I would think something further forward such as the yoke seal would be more obvious as to the source. Not sure though.

 

[Justshootme84]

That's good advice, thoroughly clean the area around the leak. Oil or gear **** will not run uphill, so you should be able to trace the leak from the bottom if you have a trail. My rear axle was covered with an inch of myd and sludge, and took a while to clean it. The tire cleaner setting at the local car wash has some good degreaser for such a task. If you have a digital camera, post up a pic or two if needed.

 

[Desert Donk]

After cleaning and filling the rear end I found I have leaks in both the back plate and from the yoke seal. The later being the worst leak. In fact when I got underneath and spent some time cleaning really well I noticed where the yoke leak has slung 90W in an arc around the underside and everything in it's path. The exhaust has some great colors from the red dust, burnt 90W and assorted grunge. Laying there I could imagine being on the crew cleaning the Sistine Chapel.

 

[cjbronco]

Yeha cleaning it would be the easiest way of figuring out where the leak is coming from. A body of mine has a 1986 bronco , and he said I can take the rear and the front dana out of it. Now, its probably been sitting in this yard for about 10 years. Im planning a road trip down to N.C.(about 12 hrs from the N.J. COAST). It doesnt appear to leak, but it has been jsut sitting. Do i take th risk and swap it and test it out, or just keep the housing and replece all the bearing, seals, shims,gears ect.? Also, do ay of ou guys know if the front dana's on an 82' & 86' ar the same? /emoticons/[email protected] 2x" width="20" height="20" />

 

[Broncoholics]

Good to hear you found the leak. I was going to say another good wy to find a leak is go thru a few mud holes and drive a few miles. The oil will really show up with thru the mud on the diff. :lol:

 

[Justshootme84]

cjbronco, if the axles have been sitting undriven for 20 years, I would not drive 1000 miles without a complete overhaul. There are just too many seals, bearings, brakes, etc. to trust your life to, especially without being road tested for a while. The Dana44 front TTB axle is the same for 82 and 86, but the gear ratio may be slightly different. To match the rear axle, the 82 should have a 3.50:1 ratio, whereas the 86 should be 3.55:1/3.54:1. What did you find out on the rear axle leak??? Pinion seal???

 

[88pimpin]

If you have a leaky rear, wear a diaper. /emoticons/[email protected] 2x" width="20" height="20" />

(Sorry, I had to. I thought it to myself everytime I saw it. I had to post it.)

 

[cjbronco]

No i still havent foung the leak, but i am just going to take out the other rear that i can get my hands on for free. im also going to take the front dana 44 aswell. now, i havent taken a rear completely out, whats the easiest way to remove and swap...? yeah overhauling would be a good idea, im just not sure if im up to do it myself....?

/emoticons/[email protected] 2x" width="20" height="20" />

 

[Broncoholics]

Take the u-bolts off, disconect the driveline, brake line and shocks, its out.

 

[cjbronco]

sounds good enough. is it worth putting some stainless steel lines on then since i have to disconnect the brake lines newayz...? I think im just going to see how much a local shop can rebuild it for me just to make it safe. Also, idk if its of importance to any of you, but on the ford-truck.com site, some guy turbo charged a 300 4.9. using a diesel turbo. pics should be up soon. /emoticons/[email protected] 2x" width="20" height="20" />

 

[cjbronco]

I am taking off the rear off of the 86' tom. When it comes time to open it up, i hvae to figure out wether or not its non-trac lock or if it is trac lock. When i reorder an overhaul kit, should i reorder the same thing even if i might be putting in an auburn lsd...?

/emoticons/[email protected] 2x" width="20" height="20" />

 

[Broncoholics]

If you do get it overhauled get a Posi or locker so you have the traction in the rear when you need it. This should be added durring the ring and pinion installation. If you pull trailers with your Bronco go Posi, a locker will break axle shafts with all the weight on the tires with load applied, same as a spool.

 

[88pimpin]

You should be able to tell if it's posi or not when you lift it up. Someone said that if you spin one wheel, and the other one moves the same direction, it's Posi, if it moves the other direction, it's trac lock. (Correct me if I'm wrong.)