Outer Limits 4x4 Board

G'day all,

Has anyone broken, or know of some who has, a Salisbury diff, 4.7 ratio. If so how and where did it break, i'm not worried about axle stregth thats an easy fix.

GURU wrote:G'day all,

Has anyone broken, or know of some who has, a Salisbury diff, 4.7 ratio. If so how and where did it break, i'm not worried about axle stregth thats an easy fix.

If you are REALLY worried about diff strength, you can always change to other style gears like Yukon etc. I am pretty sure that POS has them in his Salisbury housing in the rear end of Sam's/POS's buggy.

I am certain that Sam can enlighten you as to what is needed to change them over.

Micka

Bill mentioned that he knew someone with an FC101 that broke a 5.57:1 ring and pinion, then swapped to 4.7:1s and hasn't broken them.

Dan Dibble used to run a rig with 42's, D60's and 6.17:1 ring and pinions (which should be weaker than 4.7's). He broke a few, but not many apparently.

does the gearing have that much effect on strength,
does this come down to less torque on the diff from the engine trying to drive the wheels or is it because the amount of metal the gears have on the gear faces . i.e finer splines different cut or less splines but thicker cogs.

Rangie ute on 38'' wrote:does the gearing have that much effect on strength,
does this come down to less torque on the diff from the engine trying to drive the wheels or is it because the amount of metal the gears have on the gear faces . i.e finer splines different cut or less splines but thicker cogs.

AFAIK the main factors are: Pinion head diameter (which governs number of teeth in contact at each time), and teeth thickness.

Lower ratio gear sets usually have smaller pinions and fewer teeth in mesh at any one time, which makes them not as strong.

Are D60 CW/P's a straight swap?

MADZUKI wrote:Are D60 CW/P's a straight swap?

AFAIK...

D60's use 1/2" ring gear bolts, Salisbury use M12 (12mm). There are also some slight differences in pinion bearings and pinion spline (so you need a D60 propshaft flange).

Rangie ute on 38'' wrote:does the gearing have that much effect on strength,
does this come down to less torque on the diff from the engine trying to drive the wheels or is it because the amount of metal the gears have on the gear faces . i.e finer splines different cut or less splines but thicker cogs.

Yes.

For the same torque at the pinion shaft, the tooth load on the smaller pitch dia pinion is higher (torque = load x radius).

For same size (pitch) teeth, as the number of pinion teeth is reduced, the allowable tooth load reduces. The tooth thickness will be the same at the pitch dia, but is less at the root, where bending stresses are greatest.

As the ratio changes, it is common for larger, stronger teeth to be used for higher gearing options. (I don't know particulars of when this occurs with salisbury).

The rear diff in the Sam/POS buggy has 35 spline axels from McNamara in it and Rover hubs/spindles that were machined out to take them. The front also has Rover hubs with 35 spline axels and uni joints from CTM Racing.

Not sure if the 4.7 Salisbury has side gears available to accept 35 spline axels, and I would presume that is why they went with the 5.38:1 Yukon diffs.


Micka

ISUZUROVER wrote:

MADZUKI wrote:Are D60 CW/P's a straight swap?

AFAIK...

D60's use 1/2" ring gear bolts, Salisbury use M12 (12mm). There are also some slight differences in pinion bearings and pinion spline (so you need a D60 propshaft flange).

To add to this - a quote from Bill (portalrover/daddylonglegs/agrover/billvanwinkle) from another site

Dana 60 ring and pinions can be fitted to Salisbury's. You need to drill the carrier bolt holes out to half inch diameter. the outer pinion bearing cone needs to be changed, and the propshaft driveflange from the 60 needs to be used. (delete flange from Rover propshaft and secure uj by the 60 style ''U''bolts.)
can't tell what country you are from but over here in Oz 4.1 ratio Dana 60 rear axle assemblies can be sourced quite easily and cheaply from many of the Dodge and International light trucks that were sold in the 1960's and 70's
Bill.

[ The front also has Rover hubs with 35 spline axels and uni joints from CTM Racing.





The front actualy runs the dana stubs and hubs not rover.
SAM

TEAM KNECK wrote:[ The front also has Rover hubs with 35 spline axels and uni joints from CTM Racing.





The front actualy runs the dana stubs and hubs not rover.
SAM

I was told Rover.

Pretty sure that the centres for the wheels were lazer cut to Rover PCD.

Not important anyway.


Good to see you climbing higher on the podium in Rock Crawling though, Sam. The way you are going, you should take out the finals.


Micka

Only the Haultech boys can tell us exactly. But the first set of Sals/D60 axles they built started as a sals rear and a D60 front. The rear was fitted with 35 spline Jacmac axles, flanges, and jacmac spindles that let you run rover hubs. The front had dana/spicer axles, and no idea what stubs and hubs.

The axles were running D60 35 spline ARB's AFAIK. That means they have 0.5" ring gear holes, not 12mm like the sals 4.7 ring gear. So maybe they are running D60 ratios because that is the ratio they wanted, or because they didn't want to put 12mm bolts in 0.5" holes - but plenty of people have done it. Anyone from Haultech reading this???

Yea - the rear is just a salisbury housing with D60 locker and d60 gears. The salisbury housing just takes a different pinion bearing (one next to the yoke) and everything went straight in.

The front is totally chev D60 with a redrilled wheel pattern to convert to rangie to match the rear salisbury.

Ended up running d60 ratios (5.86:1) because we wanted this ratio.

Im just about to build up some 4.7 Salisbury diffs into 35 spline front and rear diffs for another buggy. Just going to stick some 35 spline hemispheres in there and do a jac mac 35 spline conversion on the rear running rover hubs and stick some Dodge unit bearing outers on the front. The only thing I am worried about strength wise is the course pinion flange but I think its big enough to not be a problem.

I think that with 35 spline cromo shafts the weakest point will be the salisbury crownwheel and not the pinion shaft and if thats the case everything will be fine.

On the same point has anybody got a line on some complete 4.7 salisburys with decent gears and bearings....sort of having trouble finding some?

Sam

Strange Rover wrote:Yea - the rear is just a salisbury housing with D60 locker and d60 gears. The salisbury housing just takes a different pinion bearing (one next to the yoke) and everything went straight in.

The front is totally chev D60 with a redrilled wheel pattern to convert to rangie to match the rear salisbury.

Ended up running d60 ratios (5.86:1) because we wanted this ratio.

Im just about to build up some 4.7 Salisbury diffs into 35 spline front and rear diffs for another buggy. Just going to stick some 35 spline hemispheres in there and do a jac mac 35 spline conversion on the rear running rover hubs and stick some Dodge unit bearing outers on the front. The only thing I am worried about strength wise is the course pinion flange but I think its big enough to not be a problem.

I think that with 35 spline cromo shafts the weakest point will be the salisbury crownwheel and not the pinion shaft and if thats the case everything will be fine.

On the same point has anybody got a line on some complete 4.7 salisburys with decent gears and bearings....sort of having trouble finding some?

Sam

Thanks for all the info Sam, any more info on the front - Dodge knuckles???

ISUZUROVER wrote: Thanks for all the info Sam, any more info on the front - Dodge knuckles???

Nothing special about these - just what I got lying around.

Sam