Muddy goose
Active Member
When I did that to check the noise I had no drive
Muddy goose
Active Member
Well only as test drives lately, I so hope I haven’t buggered the transferbox
Muddy goose
Active Member
Just counted the teeth on the back diff and it was RRC and it is 4.7 so perhaps the front diff when I take it off this weekend will be a 3.54?
Do I make the match with 3.54’s, will that improve mpg and keep the revs lower on the v8?
I
Do I make the match with 3.54’s, will that improve mpg and keep the revs lower on the v8?
I
tomcat59alan
Well-Known Member
Happened to a guy I used to shoot with he got a recall on his VW toe rag V10 they'd put a wrong axle on it during building,it was from the smaller engined diesel variant.It went in and had the axle, gearbox, transfer box and all tyres changedYes count the teeth on the crown wheel and the pinion then cross reference
different diffs would kind off make things go a bit funny
£££££££ There had been a storm and a tree branch had broken his door mirror,He priced one and trade was just under a grand plus the dreaded.When he got the call to pick his car up the service manager apologised and said they had to fit a new mirror because it must have been broken in the dealers compound. he inquired what happened to the old tyres ,they still had them and put them in his boot, they'd done less than a thousand miles.Happy days
Interesting question that. I guess if you do a lot of long journeys that makes sense if you do a lot of stop / start stuff then the 4.7 might be better although it also depends on which gear you end up in at the speeds you normally drive (30mph, 60mph, 70mph?) and how close it is to max torque at those speeds.
You're posting in the wrong subforum, it's freelanders that have the monopoly on different ratio diffs and the ensuing transmission windup issues.
You'll need to engage centre difflock to make it drive with only one prop.
I've run the numbers through a spreadsheet I've made, here's your speeds / RPMs with a LT95 and it's 1.11 ratio integral transfer box with the RRC's 205/80R16 tyres and 3.54 diff's fitted:
Here's the same numbers with a 4.7 ratio diffs:
You'll knock 1058RPM off of on a motorway at 70mph speed. I don't have dyno data from 3.5 RV8 as is in your motor, but I've plotted these speeds against a 4.0 TVR v8's dyno:
I'd imagine the TVR engine will make more power than your 3.5 does, but the curve would be similar shape, just shifted upwards. Anyways, as you can see, the (TVR) v8 isn't knocked out of it's powerband by the change in diff ratio, so I'd say go with the 3.54 diffs, save fuel, and enjoy the vehicle more often and less expensively.
Here's the same numbers with a 4.7 ratio diffs:
You'll knock 1058RPM off of on a motorway at 70mph speed. I don't have dyno data from 3.5 RV8 as is in your motor, but I've plotted these speeds against a 4.0 TVR v8's dyno:
I'd imagine the TVR engine will make more power than your 3.5 does, but the curve would be similar shape, just shifted upwards. Anyways, as you can see, the (TVR) v8 isn't knocked out of it's powerband by the change in diff ratio, so I'd say go with the 3.54 diffs, save fuel, and enjoy the vehicle more often and less expensively.
Wow, quite a difference. 4.7 would be good for towing and hill climb / off road events. Not a lot else!
Muddy goose
Active Member
So now I’ve found the noise was changing the noisy diff to the wrong ratio, I’ve repaired the 4.75 diff and put back on. Now I’ve put back in diff noise sorted (loose locking tab), but now gearbox is noisy. what have I broken?
I've taken all the different covers off and all looks ok inside and no broken gears or Synchro‘s, what have a damaged by having the wrong diff in the back, wound up transfer gears, bronze in oil.
I've taken all the different covers off and all looks ok inside and no broken gears or Synchro‘s, what have a damaged by having the wrong diff in the back, wound up transfer gears, bronze in oil.
Attachments
Muddy goose
Active Member
So after lots of bruised knuckles I’ve pin pointed the Issue.
Fitting the incorrect rear diff, has wound up the diff in the transferbox of the LT95 gearbox.
So far I’ve taken apart the main box and replaced the main bearing just in case it had been overworked.
Refitted gearbox to vehicle with a new clutch thrust bearing, as it is as noisey anyway from the first installation.
Fitted front and rear prop shafts, raised the rear axel on axel stands, and ran in reverse gear to see if I could unwind the transferbox. Removed front diff and turned the transferbox front drive, still makes a clunking noise (sounds like teeth not quite matching), so that didn’t work, dam it.
looks like I need to strip the transferbox apart to see what’s damaged, all looks good from above with no visible signs of damage.
The question is, what did I damage by winding up the transferbox, would it be the thrust washers inside the diff where all the little side gears are, ir would it be the Belleville plates that have gone flat?
The LT95 certainly has me at my limits of abilities, it’s such a shame the knowledge is disappearing.
Fitting the incorrect rear diff, has wound up the diff in the transferbox of the LT95 gearbox.
So far I’ve taken apart the main box and replaced the main bearing just in case it had been overworked.
Refitted gearbox to vehicle with a new clutch thrust bearing, as it is as noisey anyway from the first installation.
Fitted front and rear prop shafts, raised the rear axel on axel stands, and ran in reverse gear to see if I could unwind the transferbox. Removed front diff and turned the transferbox front drive, still makes a clunking noise (sounds like teeth not quite matching), so that didn’t work, dam it.
looks like I need to strip the transferbox apart to see what’s damaged, all looks good from above with no visible signs of damage.
The question is, what did I damage by winding up the transferbox, would it be the thrust washers inside the diff where all the little side gears are, ir would it be the Belleville plates that have gone flat?
The LT95 certainly has me at my limits of abilities, it’s such a shame the knowledge is disappearing.
Attachments
