8" gearswap problem...

[65notch]

i was swaping out the 2.80s to 3.55s in my 8 inch today and i ran into two problems. the pinion doesnt sit deep enough(seems to need a spacer between pinion and rear bearing) AND/OR the ring gear, for proper backlash, is set way off center from where it should be. so i think i need either a spacer for pinion and ring or one or the other.

has anybody else ran into this problem? im using richmond gears

 

[10secgoal]

How far off is it ? I don't know the technical term, but there are supposed to be spacers. The 5 or 6 bolts that hold in the pinion to the carrier should have spacer(s) between it, and the carrier.

 

[65notch]

How far off is it ? I don't know the technical term, but there are supposed to be spacers. The 5 or 6 bolts that hold in the pinion to the carrier should have spacer(s) between it, and the carrier.

those adjust pinion depth. i messed aroudn with those for a long time but they dont do it enough. the pinion needs to go into the ringgear more. it probably needs to go in about 1/8 to 1/4 inch further. thats why im thinking there is sopposed to be a spacer behind the pinion itsleft

 

[thehueypilot]

You need a crush sleeve that adjusts/eliminates the gap while putting a slight preload on the bearings. It should come with the install kit for new gears.

 

[iskwezm]

the crush sleeve gets crushed at about 250 ft. lbs.

 

[1320stang]

Sounds like you should adjust your spanners to move the ring gear over.

Got any pics?

 

[65notch]

ok, the crush sleeve came with the kit, and its installed and properly tourqed with proper turning torque.

1320stang: for the ring gear spanner nuts- the ring gear was already adjusted to the proper backlash, so if i moved it any more it would kill the backlash. but you have the right idea.

here is what we did...
made some calls and found out that because of the swap from a 2 to a 3 ratio, i needed a carrier that has the proper flange for the size difference. so i bought a new carrier today, installed it and got the right backlash, depth, preload and gear pattern.
now she is in the car, i drove her a little tonight to start the heat sink process.

so anyways, now we know that carriers need to be changed which doing a swap from 2 to 3.

thanks for the suggestions guys

 

[10secgoal]

hmm, I didn't need to do that. Think it's the particular year you got ?

 

[65notch]

hmm, I didn't need to do that. Think it's the particular year you got ?

i think so. i talked to a guy at richmond first, the said something about the carrier but not a whole lot. so i called up a local diff. place and they said the problem is the carrier. from what i was told, the earlier 8" need to have the carrier changed whem jumping gear ration like i did. but the later 8" diffs have a carrier that will work on both or something. because the carrier i had to buy is out of a later model 8".

 

[1320stang]

Hmmm, it seemded to me that if the pinion wasn't deep enough by an 1/8" to a 1/4" and your ring gear wasn't centered properly, how would you know if you had the correct backlash? That being said, I've never set up gears myself, one of my buddy's owns a drag chassis shop and he does them for me and I've only watched, so all I know is from observation and questioning. I do know that when your checking for pattern, you should put some sort of load on the ring gear, the palm of your hand works okay, to take out some of the slop to see the pattern right. You can use a axle and hold onto the shaft to offer resistance as well, but the palm deal works fine.

 

[TOM B]

I have a few 8 inch rears and I checked them and found that some have a smaller pinion bearing flange and mixing them would make the pinion depth be to short for adjustments. I still have the 8 inch in my early stang with 3.55 gears and a Lock-right posi unit and I had no problems with pinion depth but 65notch is right about the change. maybe the thicker flange was for the V8 and the thinner for the 6 cylinder

 

[65notch]

Hmmm, it seemded to me that if the pinion wasn't deep enough by an 1/8" to a 1/4" and your ring gear wasn't centered properly, how would you know if you had the correct backlash? That being said, I've never set up gears myself, one of my buddy's owns a drag chassis shop and he does them for me and I've only watched, so all I know is from observation and questioning. I do know that when your checking for pattern, you should put some sort of load on the ring gear, the palm of your hand works okay, to take out some of the slop to see the pattern right. You can use a axle and hold onto the shaft to offer resistance as well, but the palm deal works fine.

we thought the pinion wasnt deep enough because of how it was hitting on the ring gear tooth. i know i have the correct backlash because i use a dial indicator and adjust the spanner nuts to acheive proper specs. you are right about putting a load on the ring gear. we use our hand or what seems to work better is stuffing a rag between the ringgear and the housing. it drags it a little better with less effort.