300 tdi towing ****

hi all hope someone can help me got a 300dti disco auto witch a run 265/75 r16 tyres all seemed fine until weekend when pulled caravan out of storage and whent off for weekend she tows like shes all noise no go butting the bigger wheels on must have changed the gear ratio has any one any ideas how to bring it back with that size wheels so so tows better cheers andy

are you sure the caravan wheels arent sticking (bad bearings )

hi yes caravan has had service and the old mans grand vitara tows it tidy my mates standerd disco tows it fine witch makes my think ive changed my gear ratio putting the bigger wheels on

been told my need to chance the diffs not sure if that would help and what ones to use anyone any ideas cheers andy

bollocks it is the transfer box ratio-how big are the wheels?

standard rims with 265/75 r16 insa turbos

j12was said:

standard rims with 265/75 r16 insa turbos

Click to expand...

that will be some of it, have you also done sedimentor and cleaned out intercooler and egr bypass?

if above doesn't cure it, think about about changing ratio

yours should be 1:22:1 the defenders are 1:410:1 and military is 1:667

egr has been blanked intercooler cleaned havent done sedimentor though racing around without caravan the truck gos like billy wizz i only noticed she tows **** at weekend when we went off its asif shes all rev no go if that helps cheers andy

i dont understand the ratio thing if i had to change transfer box what would be the best box to go for to bring it back to somewere near what it should be cheers andy

I think your a bit off the mark with this gear ratio thing. Ive got an auto and they do drop down to low gear on big hills and rev up to 3ooo, it can be anoying.Maybe adjust the kickdown ? Check the boost pipe from the turbo to fuel pump is not melted or blocked with oil. This will effect your power.

If the car runs "billy wiz" on it's own I reckon your major problem is your expectation of towing with an auto.

Does it feel like a slipping clutch with the revs going daft and not a lot of forward movement? That'll be the auto then. Try using using a bit more that usually helps.

It's not a fault it's just a fact of life of towing with a TDi 300 auto. They don't go into Torque Converter lock-up until 52mph on a light throttle. Up to that speed it's all revs so you need to nurse it up to 52 then things will settle down.

On The TD5 auto's you have TC lock-up on third as well as 4th which makes towing a lot.