LLSS

Hey LLSS guys. Can you put a 4 pinion rear end in a 180 with drop axels. Or do I need to go to 190-200 rear end to make this work. Blew mine apart for second time in three yrs on a nasty track. We are an alky making hp and torque.

You'll have to change the ring and pinion gears to use a four-pinion differential. The ring gear I.D. bore has to be machined larger to slip onto the diff carrier. If you can figure out how to do that, use your old R&P.

Split the differential in two at 100ft. Time for a heavier rear end

Won't weaken the ring gear at all.......just a matter of finding a way to grind it out. I assume it's pretty hard. You'll also have to change the right side bearing cup to fit the new diff bearing, again requiring some machining. I hope you have a brass rub block on the right side to keep the ring gear from spreading apart from the pinion....that is a must in my books.

Does the rear end housing got to be machined out for a bigger bearing carrier? What about bolt patterns

I have a 190XT rear end assy I would sell.  Just saw you are in NY. a long way from Mo.

You must have a bunch of power to break a differential. What gear are you in and what does it weigh?? Do you have any video?

So it looks like I'm going with a all new 190 rear with 4 pinion.This way I can pressure lube and install disc breaks. So now I have to speed up by 10 and 20%. does anyone have gears to put in second and third slots to do this? Or could use an overdrive kit but then still need a faster third. Any help on suggestions. Thanks. The 180 research turned up that need new Axel gears and must machine a bearing cup, but have question as to whether the 180 pinion shaft will mesh with the 4 pinion ring???

You shouldn't have trouble with a correctly assembled two pinion at 6500 lbs. in a 23:1 gear. I assume you are in direct drive? There are a few 180's running much faster ratio's at the same weight or heavier. In my mind the ratio is directly related to the ft. lbs. produced and the torque is what breaks stuff. As the doctor stated, the rub block behind the ring gear is important. I good diff pin and correct washers behind the gears is also key. Running good oil with the oil level overfull also keeps things happy.

Does it bounce or do anything that would be otherwise hard on the driveline??

No doubt a four pinion would be better. It's not gonna be a 15 minute job to make it fit.

Edited by O.P.S. Heads - 10 Aug 2015 at 7:38pm

I was told by Perry that I would have to buy the sp ecial Axel pinion gears to fit the 180 Axel to the 4 pinion rear end??

R the pinion shafts interchangable

Is your pin needled properly?? Why are you having to use the brakes so much? That may be what is shocking the driveline and breaking things - maybe - dunno. Is the stance of your rear wheels wide? That can also make them drive worse and be harder to correct. Alky superstocks have lots of power and can go straight down the track so the additional power probably isn't the only issue.

The wheel speed may have no effect on the foot lbs. applied. I doubt that spinning the differential faster is what's causing it to fail. Just because you may be spinning things faster doesn't necessarily mean you are applying more stress. Probably the opposite. You may have more HP so you can do the same job faster, but the ft. lbs. on the 370 inch alky might be less than a slower running larger cubed or twin powered diesel. We have 180's hear that always run 18:1 and sometimes run in the 17:1 ratios @ 6700 lbs. with a two pinion - no differential issues.

The next thing is that a 180 differential will spin slower(and is stressed more)than a 190 differential at the same total ratio because the final drive ratios on a 180 - 185 are faster than a 190. Apples to oranges to compare the two for this exercise.

My point here is that I think it should work. Not sure why it isn't.

Side note - 5000 RPM @ 23:1 = 4250 RPM @ 20:1 by my math.

How often do you run against the 190 and how do you two compare?

Edited by O.P.S. Heads - 10 Aug 2015 at 9:45pm

Axel gears in 180 are 16 tooth,while the Axel gear for the 4 pinion are 18 both are 21 spline inside I think. So that were Perry said I needed a diffent gear to make it fit in an 180 .

180/185 final drives are 13 teeth and 76 teeth.     190/200 final drives are 13 teeth and 93 teeth.

I believe the original set of Perry gears in our 190 were:
8.566% for a 25.606/1 ratio
17.818% for a 23.595/1 ratio
27.841% for a 21.745/1 ratio