Club 80-90 Forums

Hi, I recently bought a diesel T25 that orignally was a 1600 non turbo, but was told it had a 1900 from a Passat put in it, which runs great, no problems at all. BUT... it only does 60mph with its 5 speed gearbox and sounds like its at full revs. Can other gearboxes be fitted or is this normal for them. How fast are these things meant to cruise at? I have to cruise around bet 40 to 50mph or put earplugs in and watch the fuel consumption go through the roof.

I always start off in 2nd gear and I will sometimes pull off in 3rd, it all seems a bit odd. Any advice would be appreciated.

Many thanks, Louise

Do you know what your gearbox code is?
Has it got standard wheel tyres? if not what size tyres.

The gearshift pattern is very strange to get used to on the 5-speeds!
especially if you occasionally drive other cars as well with a 'normal' gearchange.
other T25 5-speeds will fit, and there are a few different final drive ratios, depending on what vehicle it was fitted to, [under the gearbox is a code no. 2 or 3 letters/numbers,, from which you can find out what the final drive ratio is, and what engine it was orig. bolted to]
depending what you've got fitted at the mo, you may be able to get one with a 'taller' final drive ratio, in simpler terms, it'll go faster for the same amount of engine rev's in all gears, and have a faster top speed.
eg, an 'AAP' code no. 'box has a 4.57 final drive, where-as a '3H' code no. 'box has a 4.83 final drive ratio, the lower the number, the higher the gearing, so the 'AAP' will make your bus go faster at any given rev's than the '3H' box. theres a website which explains the code numbers. hope all this makes sense, i'm sure someone will point out anything i'm wrong on. in other words, yes, other 5-speed box's will fit [and 4-speeds, but its a bit trickier i think, to sort the linkage out]

Put a 1.9 dg petrol engine gearbox in it.Change over to diesel input shaft and bell housing .Proberly need the dg gear change rods and box rear mount as yours is a 5 speed .I run a 1.6td diesel with a 2ltr aircool dk gear box runs like a dream with it .There are no problems pulling up hills with it and the revs drop for cruising at 55/60 mph.I fitted a dg petrol gearbox to 1.6n diesel to an other van and that run well with it.Theres one on flebay Item number: 290066589900 .

it prob the gear box ratio,s
so you will need to fit a DK coded 2l petrol air cooled box

fit some 225/75/15 wheels and tyres on it, its easier than messing around with box ratios, plus your van looks better..

There's a guy on here called 'oldiguana' who fitted a 1.9 diesel that had a similar problem and had to change the gearbox for a petrol one if i remember correctly, he's very helpful and only lives in Stoke so i'm sure he'll give you some advice.