screwed up rear end

[biggs92EB]

Well im pretty new to this site, but i have read most every thread in it, and intern i am now a certified mechanic. yup. so my buddy has a 92 ford f-150 with a trac loc 8.8 in it that was making serious bad noises, so big bold brave me decided i can use the info ive absorbed here to help him rebuild it, well it wasnt as bad as we thought just needed new clutches and spider gears, and wheel and carrier bearing while we were there. anyways we put it back together and it had a serious howl and vibration, so back to tearing it apart, pinion bearing was shot too and a u-joint, so after consulting someone who really knew something about the rearend we needed a ring and pinion (3.55) so all new now. well we got it all back together except the spring in between the spider gears, it fought us and fought us, finally i got onto rangerstation.com and found a thread that said you dont even have to put that spring back in, so we didnt, its all back together and working perfect, tight, and with synthetic fluid, but now it is howling again, not bad but noticeable, what gives? is it that spring we didnt put in? is this normal with the brand new gears? please someone give me some knowledgable info thank you jaydub

 

[410Fortune]

HOWLING could mean that you did not get the backlash on the gears set properly.......it could mean a bunch of other stuff too........take it to a professional, with gears if you ask, dont do it yourself......

 

[biggs92EB]

we had a guy who does it for a living line the the gears up. He put the new ring and pinion in and bolted the carrier in, we did the rest, id like to say he set the backlash but i dont even know what it is, soo What else could cause it? please throw a few things out at me, this guy charged an arm, leg, and peter just for a couple hours of his time and money is short any info is appreciated jaydub

 

[410Fortune]

You sure the noise is coming from the rear gears?

Have you gone through the break in period yet?
Did you install the Ford Friction Modifier for the L/S?

Without the modifier the L/S unit will be noisy.


What brand gears did you use, did the wheel bearings get replaced? What about the pinion bearing?

 

[biggs92EB]

every bearing in the rearend is brand new, we used the friction modifier, break in period??? could the howl just be gears breaking in?? The gears were bought oem from ford

 

[410Fortune]

yES AFTER 500 MILES YOU NEED TO CHANGE THE FLUID AND MODIFIER. Also you should not use synthetic gear lube to break in gears.

You also want to do lots of compression braking during the first 500 miles, and DONT BEAT ON IT! be gentle with the new gears.......

Compression braking (engine holding you back) will get some wear on the back side of the ring and pinion, accelerating and normal driving only wear on the front side......

The howl could be because of the new gears, but it shouldnt be too noticebale......I would call the guy who set the backlash on the gears and tell him whats going on, if he got paid to set them up then he should be responsible for adjustments.....

 

[biggs92EB]

thank you for your time. The pro is coming over to drive it and evaluate. hopefully we get this resolved, and since you said nothing about it I take it that the spring not being in there will not affect the rear end negativily, other than not having as tight of a limited slip. or is it equivelant to an open diff? thanks again jaydub

 

[410Fortune]

Sorry, I know nothing about this "spring" you speak of. To me finishing a rebuild job with leftover parts is a no no. If Ford put it in there you can bet they put it in there for a reason, they dont spend millions of $$$$ on reasearch and development so they can install useless springs..........if it was in there, it should e in there again.......

 

[FMExplorer]

Spring needs to be there. It may work without it, but it needs to be there.

Howling could be a number of things - and with OEM , it is generally something installed crooked - wether it is the ring or bearnig races - something. When the bearings were replaced, did you replace the races as well? They have to be replaced with the bearings.

Also - on pre '94 explorers, 80w-90 oil is recommended. My Haynes specifically recommends NOT using synthetic with LS's in that timeframe, although I don't now why. Synthetic lube and friction additive will not cause noise while driving straight. The modifier helps the clutches to engage while turning. Without it you may experience wheelhop while turning.

Hope this helps.
J

 

[biggs92EB]

i understand your logic there, but according to multiple threads you can do many different things to the trac loc rear end to beef it up or tone it down, the thread im referring to said if you dont put the spring (pushes clutch plates together) then there will just be less drag on the clutches during normal driving. And also it said it is hell getting it in on the 3.55 geared 8.8s this i can confirm. and hell ford does screw up! A4LD!!!! thank you 410 and have a good day jaydub

 

[biggs92EB]

Thanks FM there are new races in it but you just brought something to my attention i did not put them in a rookie did i bet they are not all the way in and say no more hell or high water we'll get that spring in. thx

 

[410Fortune]

Ford's A4LD is not a bad tranny...............it gets a bad wrap because people dont realize that auto trannys require maintenence, and because they dont last forever.

Yes it is not the best tranny, but the stock A4LD unit is pretty good, it is when it is rebuilt that the nightmares begin........

So apparentlythe spring is okay out of the diff, but I personally would rather install it and KNOW that it is right, then taking somebody elses word for it.

There are only three things I dont do on my truck, Exhaust (because it;s cheap and I dont weld good yet), Alignment (again cheap and I dont have the tools/know how) and gears......(not so cheap, but it sure pays to have somebody who knows, do it).......

The rest I will do myself..


Good luck! Hopefully it is something simple, let us know how it turns out........

 

[FMExplorer]

Biggs,
W/out the spring, you have little LS available (but you found that out )

As far as the races goes - get a set of brass punches and use them with a solid hammer to push the races in. If they are burned or scored, replace them with new ones - along with the associated bearings. Whe you are done putting the races in, be sure to clean the housing real well - you may end up with small pieces of brass in the diff...

J

 

[biggs92EB]

yeah a4ld needs more maintenence then my ole' lady. doesnt help that the cats run right next to it either i suppose. anyways the shop guy doesnt think its even the rear end he thinks that the driveline took a shot and is either out of balance or very slightly bent, but we'll find out cause they are takin the cover off and installing the spring, I like the whole DIY thing, but i am with you on this one, no more gears!

 

[biggs92EB]

thanks fm good info i asked how they put the new races in and they told me they put the old bearing up against the new race and used a broken wood hammer handle as a punch as you can imagine i laughed my ass off they swear up and down its in there flush, i bet them a cold 24oz bud its not

 

[FMExplorer]

The old bearing can also dent the new race - you never want to use hard metal on a bearing race - it can scratch or dent. Inspect those races carefully.

J

 

[biggs92EB]

Hey thanks FM these guys are standin here scratchin there heads they said it took them an hour of beatin that race to get it in im sure its as rough as a cats tounge now they are tellin me they tightened the pinion bolt as tight as they could just to make sure the race was all the way in im sure this was real good for that race and bearing also i think these guys should stick to diy things like checking air pressure in the tires

 

[FMExplorer]

I'll tell you what - don't let them back in your axle.

The pinion nut needs to be tightened to about 400 ft/lb while keeping the pinion bearing preload at about 16 in/lb. What that means is it needs to be tightened enough to compress the crush sleeve and hold the pinion stable, but not tight enough to put added strain on the pinion bearing. I guarantee you have bad bearings. If you paid this guy, get your money back.

J

 

[Texan01]

I got a question for you, Does it whine on all road surfaces? my Chevelle and my Explorer whine on grooved concrete roads and it sounds like it's coming from the rear.

If it whines all the time, I'm in agreeance with everyone above, you got a bad bearing.

BTW the friction modfier hasn't kept my LS from hopping in turns. and I used the whole bottle of the stuff from Ford.

 

[FMExplorer]

The friction modifier add friction - the more you use, the tighter your LS will operate. You should only need a few ounces in an 8.8 rear end...

J