Converting 4WD to 2WD

Harry · Post by **Harry** » Fri Feb 22, 2008 5:04 pm

Ok...I've read the factsheet and it seems to make sense...but has anyone on here actually done it?

Ongoing probs with brokend/shattered propshaft bearings have forced me into considering this drastic step.

Rear propshaft now beyond repair and my local propshaft speciakists are making me a new 'heavy duty' one with grease nipples for about £200.

cheers

H

Captainsideways · Post by **Captainsideways** » Fri Feb 22, 2008 8:02 pm

I take you have differing size tyres front to rear & its does sub 20mpg : No?

Harry · Post by **Harry** » Fri Feb 22, 2008 11:59 pm

Recommended tyre sizes front & rear as per handbook.

Averaging about 35mpg and using 50% rapeseed so a gallon of fuel costs me around £4-12p instead of £5-50p.

Calculating on cost I'm actually doing an average of over 45mpg if I was using diesel only. Now what was my topic?

Oh yes...anyone tried the 2WD conversion?

See also my thread on propshaft problems
H

londonron · Post by **londonron** » Sat Feb 23, 2008 9:35 pm

Captainsideways wrote:I take you have differing size tyres front to rear & its does sub 20mpg : No?

my answer to this is YES. what shall i do as i also have a lot of noise from somewhere which goes as soon as i lift off the throttle ? i am guessing it is the diff

Harry · Post by **Harry** » Sun Feb 24, 2008 2:13 pm

What I'm trying to find out (the purpose of this thread) is if anyone has any personal experience in converting fron 4wd to 2wd.

The factsheet talks about removing the front diff and driveshafts...but is this necessary?

Why won't it be sufficient just to remove the front propshaft and blank off the transfer block and front diff?

Londonron...could you start a seperate thred on your noise etc....I may have some suggestions about the prob but I want to try and keep this thread on track as the work needs doing next week.

Ta

H

parabat2 · Post by **parabat2** » Mon Feb 25, 2008 11:01 am

If you remove just the front section of the front propshaft, I think you will not have to blank off anything. However, all the gear will still be turning, of course.

Ralph · Post by **Ralph** » Mon Feb 25, 2008 12:17 pm

Hi Harry

If the rear shaft does again and you have removed the front
stuff it stops.

Wile I did ask about the front set up I have a feeling you have
ether you have been unlucky or the problem is at the back.

You I think run loaded most of the time, if for instance this
puts the axle more in line with the engine and the prop was
a little long it could take up all the movement on the splines
and put a end load on the prop.

Clutching at straws maybe and not a answer to your question,
I don't know but it must be fixable.

dandywarhol · Post by **dandywarhol** » Mon Feb 25, 2008 12:38 pm

Thats a good point Ralph, and one I picked up on then promptly forgot immediately afterwards

...........

What did the mechanic mean by "locked splines" in your original post Harry?

Ralph · Post by **Ralph** » Mon Feb 25, 2008 12:41 pm

What did the mechanic mean by "locked splines" in your original post Harry?

Did not see that bit, me thinks the plot thickens.

Harry · Post by **Harry** » Mon Feb 25, 2008 1:11 pm

OK..here goes

The rear propshaft is in two parts, splined together so it telescopes with the changes in the suspension.

When the first bearing failure took place in June 96 the fitter at Driveline..the proshaft specialists pointed out that there was some rotational play in the splines and they may ultimately fail at some point in the future.

Last year the prpshafts (front & rear) were off again and although no repairs were carried out to the rear propshaft it was again pointed out that the splines had play and I should consider a new propshaft.

When the bearing went last week the prposhaft would not 'telescope' to facilitate removal until judicios use of a chain wrench and lump hammer sunnenly frred it up and it telescoped inwards to allow removal.

Upon inspecting the splines it was obvious thet they had come out of alignment and jammed at sometime before or during the bearing failure and the consequent vibrations.

I suspect it happened at the same time as the bearing failure as there was an orrible bang grauncing noise during a turning round manauver in a tight space on a hill with the van fully loaded. Good grippy surface...new tyres on back...none of the usual skiddy type slippage. Put the transfer box under a lot of strain.

Hope this sheds some light

H

Ralph · Post by **Ralph** » Mon Feb 25, 2008 1:19 pm

I think but could be wrong I often am that the splines
failed and would not telescope and this led to the bearing
being under not only twisting force but fore and aft force
as well and that led to it's collapse.

Harry · Post by **Harry** » Mon Feb 25, 2008 1:22 pm

Precicely....thats why I've ordered a brand new 'beefy' shaft to be custom made. Cost around £200 then do away with the font driveshaft.

dandywarhol · Post by **dandywarhol** » Mon Feb 25, 2008 3:56 pm

Yep, makes sence now - and it would make the yokes misalign and cause serious vibration! They must've been REALLY worn to do that

The VC might be OK after all

bigdaddycain · Post by **bigdaddycain** » Mon Feb 25, 2008 8:06 pm

Having never really inspected the propshaft on the bongo, am i right in thinking that the "splines" referred to hear is what i assume to be the universal joint?

If that had locked, like ralph says, a tremendous fore and aft force would have been put on the diffs, i'm suprised its lasted as long as it has harry.

You know the loud "graunching" sound you described harry? Was it like the sound i noticed at burnley when you engaged reverse?

Ralph · Post by **Ralph** » Mon Feb 25, 2008 8:19 pm

The Universal joint allows the prop to run out of line IE if the
back axle is lower/higher than the gearbox output shaft, the
splines allow the prop shaft to vary in length as the axle moves
up and down at some point it will be in line so the distance will be
shorter if the splines are sized it would try to force the axel and
gear box apart and put a lot of force through the uj.
Well I know what I mean.