FINALLY.....The Concluding Chapter!!
Took delivery of the Patrol on Wednesday, re-fitted with the original axle, and a brand new diff center from Nissan, and it is driving perfectly!! What a huge relief to finally be back up and running.
For the benefit of anyone who is unfortunate enough to be left in a similar predicament in future, I thought I`d share a few thoughts and lessons learned...in no particular order:
1. Be very careful of second hand parts. I think these can often be a very viable route to save costs, however in this instance it led to being badly burned even though I thought I had taken the appropriate precautions (getting it checked by a diff specialist prior to purchase).
2. Related to the above, a visual check may not be sufficient to detect issues with second hand parts (particularly axles and diffs in this case). The second hand axle proved to have a bent axle casing, as well as a bent pinion shaft, however there was no visual evidence of this. When checked on an alignment machine however the rear wheels had a toe in of 18.4mm.
3. If you`re in a tight spot, there are specialists around who claim to be able to straighten a bent axle. Before the bent pinion was discovered, the axle casing was sent to such a specialist. Their work improved the alignment reading from 18.4mm toe in, to 3mm toe in, which is a significant improvement, however I would have sent the casing back had the bent pinion not resulted in me abandoning the 4.5 axle swop. The ideal spec for minimum tyre wear would be less than 1mm, whether this degree of accuracy would be achievable if I had followed through is hard to say, but probably worth a shot if anyone has the mis-fortune of bending an axle for whatever reason.
4. Conventional wisdom seems to be that if a pinion shaft cannot bend without either cracking the diff casing, or causing visible damage to crown and pinion teeth. This is not the case! When spun up in a lathe the 4.5 pinion has a distinct wobble/run out (the cause of a bad vibration on over-run when fitted to the vehicle), however there is absolutely no other visible damage…gear teeth look brand new.
5. A H260 rear axle is a direct swop into a H233B axle vehicle, the only thing that requires modification is the propshaft, which must be shortened by 50mm to accommodate the larger H260 diff casing. The propshaft will physically bolt up, but the slip joint will be maxed which will cause problems.
6. If you bargain hard and play the dealers off against each other re discounts, a new ring and pinion for the H233B rear diff can be had for around R6800 Ex VAT….in retrospect, this is a BARGAIN!! Carrier bearings and pinion bearings should be available from the aftermarket bearing suppliers, so its probably only the collapsible spacer that you would need extra from Nissan. Faced with the same situation again, this is the route I should have gone. Not doing my homework properly with regard to the Agent prices caused me to go down a 7 month dead end!!!!!
7. Rear axle bearings are difficult to obtain from the aftermarket suppliers, and are very expensive from Nissan. Rear Axle bearings are however obtainable from Bearings International (Bearing Man swore they were agent only!), however the grease seal is only available from Nissan. Good Quality (jap) rear axle bearings cost R1k per side from Bearings International, vs R2.2k per side from Nissan. Nissan will however still fleece you another R1k for the seals!!!
8. When re-installing a diff, do ensure that you refer to the shimming procedure for the actuator, outlined within the workshop manual. If the actuator is not properly shimmed, you may not be getting a full engagement of the mechanism which will lead to a increased likelihood of failure under load.
Okay…think that’s about all I can think of for now. Hope some of the hard lessons learned over the last 7 months will save some other people some hassles.
Have ended up with the remains of the abandoned 4.5 rear axle. It is not usable as a unit, however the following component parts are available and known to be good. If they are of use to you, please PM me.
- 4.5 (H260) diff carrier with spider gears and diff lock mechanism
- Diff lock actuator
- 4.5 (H260) side shafts, with R 2k worth of brand new axle bearings pressed on.
- Various other related axle parts
Cheers,
Ross