new 5 speed gear box

[jocko]

I have an 85 transporte,r converted to a camper. It was originally a petrol, but now has a Mk 3 Golf TDI engine fitted. It has a 4 speed gear box and I would like to get a 5 speed fitted. What would be the right box to fit. cheers for any help.

[R0B]

Just so you know.The five speed is no better that the four speed.It wont make any difference.

[donciuz]

You have to compare gear ratios and final drive ratio of different boxes. What is your current gearbox code?
I have a 5 speed gear box in mine and a tdi engine. I don't need gears 2 and 4 because I can easily shift 1-3-5. What I need is 6th gear and maybe 7th

[ewenmaclean]

Depending on your budget, have a talk to Aidan about getting new gear ratios - I do 70 at 2900 rpm now thanks to him. There's a useful gear ratio table here:

http://rjes.com/html/gearbox_types.html" onclick="window.open(this.href);return false;

[dash]

Just so you know.The five speed is no better that the four speed.It wont make any difference.

Depends on the box. If you go from a four-speed commercial box to a five-speed Caravelle box it's a massive difference.

[jocko]

Getting a bit confused now, I thought 5 speed was always better than 4 on the motorway and for fuel consumption. Where do I find out the gear ratio/gearbox code? Please note I am mechanically challenged.

[Aidan]

stamped on the bottom of the box on a flat area about 4" below the reverse switch housing, nearside of van forward of drive shaft
probably ABD which is 4.83 final drive 0.85 fourth gear, 5 speed would have been ABN which has shorter first gear and only 0.82 fifth so only 5% less revs for same speed
TDi makes a lot less revs, generally TDi boxes I build either have a final drive change to 4.14, and/or a longer 4th or 5th gear depending on how good the engine set up is
figure on a grand upwards for something that really does the job
you may find a 4.57 final drive box with 0.82 fifth 5 speed (AAP) but they are well sought after and peeps ask silly money for tired old boxes that need rebuilding

[jocko]

stamped on the bottom of the box on a flat area about 4" below the reverse switch housing, nearside of van forward of drive shaft
probably ABD which is 4.83 final drive 0.85 fourth gear, 5 speed would have been ABN which has shorter first gear and only 0.82 fifth so only 5% less revs for same speed
TDi makes a lot less revs, generally TDi boxes I build either have a final drive change to 4.14, and/or a longer 4th or 5th gear depending on how good the engine set up is
figure on a grand upwards for something that really does the job
you may find a 4.57 final drive box with 0.82 fifth 5 speed (AAP) but they are well sought after and peeps ask silly money for tired old boxes that need rebuilding

Cheers, you certainly know your onions. In your opinion is it worth changing to a 5 speed?

[AdrianC]

Getting a bit confused now, I thought 5 speed was always better than 4 on the motorway and for fuel consumption.

It depends entirely on the ratios. Most cars, back when 4spd was standard and 5 was luxury, had 4th about the same ratio in both, so 5th was a higher cruising gear (often called "overdrive" - which is something else entirely). If top is about the same in both, then you'll just have more options below there.

[Aidan]

Cheers, you certainly know your onions. In your opinion is it worth changing to a 5 speed?

only if it's bespoke built to do the job and or you live somewhere hilly or tow so require the lower 1st gear

as stated it's all about the ratios

if you stick a TDi in a 1.6 n/a diesel van you get a van that does 55-60 flat out which is horrible ; because the TDi doesn't want to rev much over 3000 whereas the old lump ran to 4000
Petrol vans happily run to 4000+ too - so are geared at around 3800 for 70mph - sounds a bit busy there so most of us run around 60-65 for a slightly more relaxed drive

4 speed petrol top gear 0.85, 4 speed n/a diesels are the same but have lower final drive so slower for the same revs
4 speed dieselTD top gear 0.78, ie 8-9% less revs for the same speed
5 speed top gear 0.82 is only 4% less revs for the same speed

1.7 diesel vans were meant for local work not long distance so they are geared to get to 50 really nicely but are hard work after that
1.6 diesels are slightly better but really you want a TD for long distance if speed is a requisite, but for all T3s slow is more economic, more relaxing and quieter

Petrol vans are more jack of all trades but of course now the cost of fuel means that peeps have a hankering for diesel, but if you don't do massive milage then petrol is fine just accept the fuel cost - if you want economy buy a new van (T4s and T5s aren't that economical mind, T5s are a lot cleaner though)
petrol van on lpg works if you do the mileage to justify the conversion costs and can afford the space loss internally

if you want modern performance from a T3 then expect to spend a good few grand to get an engine and gearbox conversion that does it as well as can be done, but it'll never be a T5 - T3's a 80s vehicle designed in the 70s with some 60s technology in it and that's why we love them

just my ho of course

[billy739]

if you want modern performance from a T3 then expect to spend a good few grand to get an engine and gearbox conversion that does it as well as can be done, but it'll never be a T5 - T3's a 80s vehicle designed in the 70s with some 60s technology in it and that's why we love them

that just about sums it up!