Thread: Life of Puma Rear Diff's

Originally Posted by JDNSW

I suspect that the current situation is something like this - "Salisbury axles have become unavailable - we have to find a replacement. Luckily we have one alreay in production. The P38A has a diff that is rated to handle this power and torque, and is trouble free in the P38A, which has a lot more power (not used all that much offroad or for towing, and maximum weight is less, but should be OK as a stopgap - the Defender will be replaced in a couple of years anyway). "

John

John, I actually think it was a case of the P38 style rear diff is what was fitted to the UK MoD XD Wolf's (as they can be braced/gusseted/trussed more easily to cope with overloading than a Sals) so it made sense for Land Rover to use that assembly across the board to save costs.

There was talk at one stage that the MoD may have stipulated the same CWP front and rear too for supply/servicing in the field, but I'm not sure if that's correct and the XD's use P38 style front diffs or it was just internet conjecture.

Originally Posted by nugge t

2010 110 with 55,000

No problems with diffs and I certainly wouldn't say I have nursed them especially on my last couple of trips.

I'll see your 55k on a 10 and raise you 85k on a 09

No diff dramas with mine either - and that includes a reasonable amount of heavily laden towing (20k) of which 5k was on corrugated dirt.

Having said that, mine has had a new rear centre (under warranty), which was changed out due to misdiagnose half shaft wear (i.e. the diff had no issues at all - lol) and I still intend to upgrade to something tougher (likely Ashcroft) in the future.

Well that's makes me piggy in the middle. 2010 with 70K with no problems. But given what I now know I sold the P38 locker and started building a Sals with a Detroit to replace the original. I originally bought the locker thinking it would solve the diffs issues, but depending on use perhaps not.
I hope, and no paying out here, cause I truly do, for those that have had no issues with their P38 that it keeps going as it should. But for me the $2000 to swap it over is great piece of mind when out in the sticks. Considering what I have spent already, and the potential cost of recovery, it's neither here nor there.

Originally Posted by pawl

Hmmm after reading this thread and another about puma reliability I think I will pass on an 09 Defender with less than 30,000kms on I was interested in. It appears to me, this just isn't an isolated problem, it is very common and once they are out of the warranty period it is time to off load it. Very disappointing

Just find a diff specialist who knows what he is doing and can set it up right for you and you will be OK .

I disagree. They are not up to the task at all. Structurally the banjo housing when braced seems to be a winner as they flex better than a Sals, but the centre leaves a lot to be desired. Either fit a Rover housing and upgraded rover centre (ARB, Ashcroft etc) and some decent axles , or a Sals and you will be fine.

I have seen quite a few P38 diffs in Defenders over the years last OK, but me personally? I wouldn't rely on it at all. Even locked ,and 4 pin etc they still have that weak crownwheel to pinion design.

JC

some info I stumbled across on another 4x4 forum...the big dogs putting their "Built" diffs through hell (think D60 and 14b), some have found that ring gear failure was not due to the pinion moving as first thought, but the carrier actually flexing...

Now I know this is not apples to apples, but it could be an issue???

In NO WAY am I defending the P38 diff, but really for most, a P38 diff with ashcroft center and set up correctly will probably give many years of trouble free service.

I wouldnt be suprised if Ashcroft are working on a better R+P as the numbers of these diffs increase with LR sales???

Sals have there cons also...

Originally Posted by justinc

I disagree. They are not up to the task at all. Structurally the banjo housing when braced seems to be a winner as they flex better than a Sals, but the centre leaves a lot to be desired. Either fit a Rover housing and upgraded rover centre (ARB, Ashcroft etc) and some decent axles , or a Sals and you will be fine.

I have seen quite a few P38 diffs in Defenders over the years last OK, but me personally? I wouldn't rely on it at all. Even locked ,and 4 pin etc they still have that weak crownwheel to pinion design.

JC

Until Ashcroft release their replacement centre...

Ahem, cough...

Originally Posted by uninformed

some info I stumbled across on another 4x4 forum...the big dogs putting their "Built" diffs through hell (think D60 and 14b), some have found that ring gear failure was not due to the pinion moving as first thought, but the carrier actually flexing...

[snip]

Which is what diff pegging stops

(image pinched from Ashcrofts website. Hopefully Ian and Dave don't mind )

Sals have there cons also...

Scurrilous rumour put about by rear Rover and P38 type diff people who merely suffer diff envy