Vito 115cdi diff ratio change

[pipes66]

Hello,
I want to change my diff to a 36:11. I'm not sure what I've got at the moment, I'm assuming it's a 41:11. I've noted at 2k rpm I'm doing 56mph,2500k-73, 3k-86mph. Has anyone else done this before,will I have any problems if I do?
Many thanks.

 

[wu56Shoozz]

Good Question here. I have a 111CDi 2006 and wondered the same thing - what do I have as I may need to replace it very soon...

 

[Dave Hardwick]

I have a 115 sport and according to the build data (there is a link in "Favourites", type in your chassis number and find the spec of your vehicle)

I have a 3.2 ratio diff' (36:11). At 2000 RPM the speedo is showing about 60 MPH. I can check other speeds iff you like and against a GPS if required?

Dave

 

[sparkydude]

If anyone needs their datacard msg me your VIN and i will send it to you , sometimes the russian sites are not all that reliable .

Nick

 

[StMarks]

Fwiw I think my 2007 109cdi shows about 3k at 70mph.

From what I have read 109s have a 3.727 ratio back axle, presumably needed to shift nearly 3 tonnes gross weight up any sort of incline with just 90 bhp.

The more powerful 111 and 115 had 3.273, with 3.455 as a 'low ratio' option.

Both the 111 and 115 apparently therefore give better mpg & lower emissions than my 109.

The 120's back axle was 2.923

Hth.

 

[VinDeisel]

Can we put the 2.92 into the 115, has anyone done this

 

[VinDeisel]

Can we put the 2.92 into the 115, has anyone done this

 

[Simonjustextreme]

I

Can we put the 2.92 into the 115, has anyone done this

have just done this to my 115,
Ratios are great, but I got an immediate limp mode as soon as I got into 3rd,
Scan tool said “incorrect final drive ratio”!!!

 

[m80]

I

have just done this to my 115,
Ratios are great, but I got an immediate limp mode as soon as I got into 3rd,
Scan tool said “incorrect final drive ratio”!!!

This is something I was considering.
Interesting as to how it would know and why it would worry about it.

 

[VinDeisel]

You’ll have to code it now with the star tool

 

[MrBlonde]

Evening,
Inside the sump pan on the auto gearbox is two modules that pick up the speed of the gearbox RPM. If these dont match the values set by the ABS rear wheel wheel sensors, it will pull away change up fine then get stuck in limp mode third gear. I tried every ratio when I blew min up at at high speed. I tried 41:11. 38:11 anything to get it back on the road. Nothing would work. It had to be 36:11 or it would go into limp. I'm sure this could be changed using Star. Or just put the right one in and go up on tyre size 17/225/55 to 17/225/65 to give a greater rolling radius= Higher top speed.
And if yours is sport the higher softer sidewall tyre would be a welcome release from the sport rock hard springs.
Not sure if you would have to change the fronts as the ABS might throw a wobbler as they will turn faster then the rears. Have gone up real big in the past on W202 with no problem. Same with A210 AMG yes it goes faster but sits like a Range Rover.

 

[VinDeisel]

Mmmm yes when you only change the rears to a higher tyre and not the fronts, the cruise control will not work.
My friend has service centre and new flash code machine so I’ll put the 2.92 in & then tell the ecu/speedo it has the 2.92 diff not the 3.27

 

[MrBlonde]

Sometimes the label on Top of the diff gets jet blasted off so you cant see the ratio. One way to check for sure is take the prop 4 bolt flange off and on the end of the diff that has the big nut on it, the ratio stamped into the shaft.

 

[VinDeisel]

I purchased the V6 diff 2nd hand from shop here in Aussie. They are 2.92

 

[MrBlonde]

I would be interested to no how this turns out. As I bought the right type 3 times the 36:11 and they all made terrible noise. Got the job down to 40 minutes to get it out in the end without even taking the wheels off. Your new one 38 Crown 13 spigot should bring the revs down.
I have been chasing a "Sonic Boom" at 80mph on power for 3 years with mine, Diff swap 6 times. Changed prop bearings first then the whole prop.Complete exhaust. CAT joints,turbo clamps. Engine mounts,Gearbox mounts. Added the Harmonic balancer to the the rear diff. Gearbox oil and filter made no difference.
I noticed a 400rpm drop before when when I up sized the tyres so hopefully your new diff will do the same and be silent. Rebuilds on these diffs are limited to bearings only as nothing else is available (like worn out planet gears) very visible with the the cover off.Also the large outer driveshaft bearings move in and are not held with a brace over clamp.
Having to STAR it up and find its a rumbler would be very disappointing.So hope all goes well. Your choice of oil may play a part latter on if its hot there.
I had to use a digital lazer temp in the end to find out if the diff was anygood and not suddenly lock up at 70mph which is scary as hell believe me(like someone stamping on the hand brake!!). MB oil is very thin for better MPG and in someway gets to the parts faster for lubrication. But if the diffs done a 100k its only got 30k left. Tried loads of Oils and settled straight 140. Thick as hunny and takes 5 miles to thin down but at least its 45-55c instead of burning your hands to touch the diff 75c. Used a coke bottle with compressed air to get it in" Its thick.

 

[VinDeisel]

Far out that’s full on, in AUSTRALIA we have a couple local oil companies that make nice thick oils that are synthetic.
I worked out it’s about a 11% drop or rpms going to the 2.92.
So 100kph @ 2260rpm should go to 2040rpm genuine gps speed. Hopefully going to a 215/65 16 will take that to bang on 2000rpm

 

[VinDeisel]

Potential top speed should go from 186kph to 210kph with the diff and slightly higher tyres. @ redline in top Gear 4200rpm

 

[MrBlonde]

Roll a tape measure around your tyres. Mine are 2 meters 20cm. And Mine Does 122mph 196 kph screaming its nuts off. I have fitted rear airbags and lower them for that speed to stop body roll as its feels like its going to roll on fast motorway bends or off ramps. Mine does have a inline tuning chip.

 

[m80]

Tire Size Comparison

 

[MrBlonde]

Tire Size Comparison

Thanks for that.I had that website on one of my laptops and wanted to show how one size up subject to clearance does make a difference. Nearly 7mph at 90mph.