MK1 diff axle ratios with Mk5 engine and gear box

[BettyCamper]

Hi everyone,

I have been rebuilding a transit MK1 twin wheel based camper for the past 5 years, I have put a 2.5 Mk5 gearbox and engine in and the rear axle sounds terrible, so, I need to get this rebuilt but at the moment it is only managing about 45mph with revs through the roof, so I want to change the gears. My understanding is the MK1 is a 5:14 and the Mk5 (which was only ever happy at about 60mph) was a 4:63. What is the lowest I can go? Would be nice to cruise at 60mph without sounding like I have a generator in the passenger seat. I have attached some photos. Any help would be much appreciated

[dumper]

I had a mk5 100 l it came with a 5.something Can’t remember exactly I fitted a 4.63 and to be honest it seamed about right for the power of the engine I wouldn’t go for a 3.something diff not sure what’s available for twin wheel mk1 but you may get something in between.
Has for your top speed of 45 mph you speedo will be out none of the mk1 twin wheel vans we had did less then 60 mph even the A series 190 pickups with a 2.4 York engine would do 55 mph

[DougT]

Best bet is to follow Ken B's method of fitting later CW&P into Mk1 axle.

viewtopic.php?f=3&t=111158

Cheers

Doug

[Ralph.9]

I have couple of 4.63 MK1 or MK2 twin wheel rear axles.

[BettyCamper]

Many thanks for the replies so far, I will look into the Mk6 way as a possibility, does anyone know the lowest ratio available on these?

[Muttley]

Do you mean the “tallest”? Lower means slower

[BettyCamper]

Sorry Mutley, I did. I also reread what I had written, what I want to know is what ratios are available for the twin wheel MK1 axle and the Mk6 setup?
DougT did you follow Ken's method?

Many thanks

[Ralph.9]

I have a 4.63 MK1 or MK2 twin wheel axle if your interested?

[BettyCamper]

Ralph, how much are you looking for, for the MK1 4:63?

[Ralph.9]

I have pm'ed you.

[DougT]

Yes I did. But If I remember, the CW&P was advertised as a Mk5 and I found that the Mk 4 propshaft flange fitted.

It appears that the CW&P is the same for all twin wheel axles apart from Mk1 and Mk2 which have the smaller dia splined connection to the propshaft flange.

There are very limited ratios for the twin wheel axle with 4.63 being the best you can do for higher road speed at lower revs.

Doug

[conrod]

I have a Mk7 axle (same as the Mk6 I think, except it is disc braked) which I am putting into my Mk2 soon. It is a 3.58 ratio. Tallest is a 3.31 ratio. But I think either of these would be too tall for your 2.5 Di. It just won't have the torque to hold top gear.168Nm is pretty weedy by modern diesel standards, my 2.0 Mondeo diesel makes 450Nm!

For a camper, 4.63 would be about right. Just buy a complete axle from Ralph and sling it in, by far the easiest way to go!

[DougT]

Hi Conrad,

Just for future reference, if you do happen to have a look at the internals of the Mk7, it would be interesting if you could compare the CW&P between the Mk7 twin wheel and the Mk2 twin wheel which I know is very familiar to you......

If Mk7 happens to be a modified Mk6, does this mean Mk7 internals would fit in Mk1/2 somehow, ie just CW&P or plus other bits. Your thoughts would be very interesting.

Thanks

Doug

[conrod]

Hi Conrad,

Just for future reference, if you do happen to have a look at the internals of the Mk7, it would be interesting if you could compare the CW&P between the Mk7 twin wheel and the Mk2 twin wheel which I know is very familiar to you......

If Mk7 happens to be a modified Mk6, does this mean Mk7 internals would fit in Mk1/2 somehow, ie just CW&P or plus other bits. Your thoughts would be very interesting.

Thanks

Doug

Hi Doug,

okay will do. I have already had the back off the Mk7 axle, but did not measure anything. Key would be if the crownwheels are the same diameter, then go from there.

cheers Conrad

[BettyCamper]

Many thanks for the info Doug, I still have the Mk5, luckily I had not scrapped it yet. So, going to open that up and see if I can use.

Cheers everyone for the information.