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TR4/4A R200 Differential Upgrade

RJS

Jedi Warrior
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Hi All,

So, some of you have probably seen my recent post on axle shafts. My reason for posting was due to rear end clunks when pulling away from a stop in 1st gear. I had the differential rebuilt 4,500 miles ago (as well as confirming condition of diff mount pins and renewing all the diff bushings). That being the case, I suspected u-joints or splined axle shafts (dismissing the idea it could be the diff). I pulled the hubs and axle shafts this weekend. Granted there is a minor bit of play in the u-joints and splined axle shafts but, hardly enough to give the loud clunk I am experiencing.

So, I am wondering if it could be the differential again? I was considering CV joint axle shafts but now I am wondering if my money would be better spent on a Nissan R200 diff upgrade. Questions:
  • How can I test my current differential for excessive play or lash? It is mounted in the car with axle shafts disconnected but, drive shaft is still connected
  • It is reasonable that my diff (rebuilt 4,500 miles ago) could be suffering excessive lash again so soon? (thus confirming it is a weak unit from the get-go and reinforces my decision to upgrade)
  • For those of you who installed the R200 differential upgrade, would you say that that change alone solved your clunking issue?

I did play with the differential a bit but, not sure I was testing it correctly. If I grab the two output flanges and rotate, there was barely 1 degree of rotational play. But, on the input flange, there was probably 3-4 degrees of play (which seems excessive to me) and a fairly audible clunk when it met its stop.

Thanks

Bob
 
Hi Bob

You have to remember that you are putting about 360ft/lb through the diff in first gear and about 1300ft/lb through the drive shafts. I nearly give myself a hernia tightening the nuts on the (CV) driveshafts to 100ft/lb so you need to take the much greater force into account when testing the diff or driveshafts. If the diff was done by reputable people it would be surprising if it had gone in 4500 miles. You have previously said that you can feel play in the driveshafts when you test them by hand. I would be contacting the diff people first and asking their opinion but if the driveshafts have never been rebuilt, that is where I would be looking. I had my diff rebuilt 12,000 miles ago and it has a bit of play in it, but with the CV driveshafts, I do not get any clonks. You get a much smoother drive and ride with the CV shafts and no lock up under power which can cause suspension problems with the standard shafts.

Regards
 
Thanks Rocky,

The diff was rebuilt by a dedicated British driveline specialist here in Connecticut who gets work from across the country. He does nothing but transmissions, overdrives and diffs for LBCs - alot for guys that race their LBCs too. Here is the write up from his invoice:
"disassemble, clean, inspect, replace worn parts, re-clearance, reassemble, paint, test differential. Drill and tap case for drain plug. New parts include: 2 side axle seals, 1 front pinion seal, replace differential pin (pinion shaft), 2 carrier bearings, spider shims, pinion shims. Crown & pinion good. Front & rear pinion bearings good."

So, you may well be right and I will call him tomorrow and see what he has to say.

Bob
 
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