Now that I got my new clutch and the Mazda tranny is working fine, what to do about the howling rear end? I thought the howl was the tranny, but my mechanic informed me it is the rear end. He said it is somewhat worn but a long time from going out. The noise is annoying though. I wonder if there is a different lube that would quiet it? (I should ask this after already getting in trouble trying different lubes in the tranny.) Or is there a noise proofing coating or something? I thought of wrapping the pumpkin in insulation, but figured that might make it overheat--hmmmm, maybe those plastic packing bubble sheets?

 

IF your rear end is howling then you have a bad beraring in it. You need to take immediate action, as if the bearing freezes up you will break the pinon. You first need to find wheather it is it the pinon or an axle bearing. Then replace accordinly.

Dave

http://a2ztowing.homestead.com/a2ztowing.html

 

Never ignore a noisy rear-end! It can totally destroy itself and be very expensive to repair.

Take it to a good 4X4 shop and have them service the rear-end (not a dealer). They should check the gear lash and other things and replace the fluid. Make sure they use the ford frition additive if you nave the ford LSD (trac-lok).

A rear gear set can be noisy and not go bad for a while, but a bad bearing won't last too long especially since you say its loud enough to be annoying.

Check it soon.

Randy

BTW-Mine was noisy (kind of a clunky noise while turning) and it turned out that the carrier was cracked and eventually broke loose destroying everything but the pinion and ring gears in the diff. Cost of replacing just the carrier was $200 (parts) and a weekend of sub-zero finger-freezing work. Not fun.

 

Thanks for all the advice. I probably should just change it as it is a 3.08 and since I sometimes tow a 3.55 would be advantageous. The howl has been going on since I got is and dosen't seem to get any worse. I don't notice it if the radio is turned up a bit past half way. My mechanic said the gears are worn but that I had a long time before it would go out (this in light of a pending trip to Yellowstone with trailer) and that it would get a lot louder first. It starts at around 30 mph or so and stays with all the way on up although there are spots it seems quieter, such as maybe around 55 and 75 mph. It only whines under load. As soon as I let up on gas it is quiet as can be, which I think would indicate gear wear, as a bearing should continue to whine in that situation, right? If I do change the gear, can a traction lock go in the same case?

 

guarantee it's the pinion bearings have replaced many 8.8 and 7.5 pinion bearings for that exact problem. Has anyone ever done a pinion seal on it? If you replace the seal you must be very careful when you torque down the yoke since the crush sleeve is already preloaded (crushed). If you over tighten it you will after a short time have a noise , worse when under load. The dealer would be the best place to take it they have all the specail factory tools it requires to properly set up the rear axle. It migth cost a little more but you know it's done right and there will be a parts and labor warranty.

 

Agree with your analysis...disagree with "dealer."
A dealer will send the rearend out to a specialty shop.
Save yourself the dealer's markup and find out what shop the dealer (and other shops) send their stuff to.
Eddie

 

I talked to my mechanic again. Apparently I misunderstood him before. He says the howl is the pinion bearing. He still is confident that it will be a long time before it needs to be replaced and that it will not leave me by the side of the road. He said that when it gets really bad I will start feeling slop or a clunk when I start/stop. I told him that I would like to change from the 3.08 to a 3.55 for towing and he said we should get a whole assembly from a scrapyard (along with speedo gear). Going to check some prices/availability today. And I am hoping to go limited slip.

 

Finding a good 3.55 LS rear-end in 8.8 is like a needle in a haystack around here at least. The 3.08 is the most common and easy to find. I only found one 3.55 LS carrier in the entire Milwaukee, WI area and he wanted twice what it was worth.

I finally found a good carrier only from a small place that upgraded someone elses truck to an Eaton locker.

Luck of the draw.

Randy

 

Your mechanic is WRONG. Once the bearing starts making noise it will only get worse. You should have the bearing changed ASAP. The noise is coming from pitting on the bearing surface. You might end up getting metal shavings and causing much more damage. I am a professional mechanic with 18 years experience. I know what I am saying.

Dave

http://a2ztowing.homestead.com/a2ztowing.html

 

Thank You, I am searching for a used rear right now. I can get limited slip 3.55 for $650, but am looking for lower price. One place would go $400 but doesn't have it. I will keep looking. It has been howling for 5 to 8 thousand miles so far, but it sure makes me nervous thinking about a long trip with it.

 

Ok. How do I know it is a pinion bearing and not the gears? Maybe some shims would help. According to the website for West Coast Differentials, "noise during acceleration at all speeds can be caused by bad ring and pinion gears or by a bad rear pinion bearing." That is my problem. I think my mechanic should remove the cover and take a look at what is going on before going for a rear end swap.

 

yeah that howling is annoying.

my tranny has been doing it in overdrive now for 6 months and 10k miles. just waiting to blow the dam thing up...then I can put my toploader in it!


but what ever you do...get it fixed. unless you don;t mind spending money!

 

The only way to find out is to take it apart. But I believe that more than likely it is the pinon bearing and not the gears. If the bearing allows the too much movement then the gears will be damaged.

Dave

http://a2ztowing.homestead.com/a2ztowing.html

 

Replace the pinion bearing as well as the ring and pinion (put in your 3.55s). The whine is the ring and pinion. You now have a bad wear pattern on them which could have been caused by a bad pinion bearing, which is letting the pinion get loose, as has already been suggested. If you just replace the bearing you will still get a whine from the ring and pinion. It will not go away. Diversified Marketing in Michigan has new Fordmotorsport 8.8" 3.55s, 3.73s, and 4.10s for $149. You will also have to replace the pinion seal, crush sleeve (comes w/the new ring and pinion), bearings, and get new shims. Best thing is to buy a kit though I bought all the parts separately. Buy your traclock at the same time and have it all installed at once. With the exception of the traclock (I'm not sure how much they cost and labor cost), everything else including fluids (gear oil and friction modifier-(if you use the traclock)) and parts and labor should be around $400. Do not put in used gears. They will already have a wear pattern on them and you have about a 99% chance that they will whine. Been there, done that. Go back with new Ford gears. FMS gears are the least likely to whine (new) out of other gears such as Richmond, Zoom, Pro 5.0, and Motive gears though there is still a chance of it just like all other gears. It also has to do with the installer but I guess you could put it as FMS are the "fool proof" of your choices. As cheap as new gears are it would be wrong not to get them.

 

Thanks, My mechanic is looking into the rear case today to see what is going on (with the exception of the pinion bearing which is only visible if pulled out). I will post the result if I find out in time (may be gone a couple weeks after today).