wots the difference between an f16 from a astra gte 8v and a f20 astra gte 16v. are the caseings interchangeable, are the diffs the same, is the gearkit the same??? some people say that the f16 is weaker but why , which bit is weaker ??? cheers
On the outside everythings the same except for the numbers. There maybe variations on the actual gear linkage design and input shaft cover, (maybe a plug instead of having to remove the whole cover). The gearboxes are basically interchangable. The GTE 8v should have an F16 CR hence geared for accelaration. The F16 is rated to 160Nm, the F20 is rated to 200Nm and is CR in design. The F20 will be less energy efficient than the F16 i.e. more losses. You can get the actual gear ratios from an haynes manual or the car manual.
the final drive and main drive pinions are the same, the gearsets are the same, externally the cases are the same, the end case bearings are the same, selector rods are the same.
the only difference i can find is the differential, the main drive front bearing and of course the selector turret/linkage.
something to consider when saying that a gearbox is rated to X is the fact that torque is multiplied through the gears, so theres a neck snapping 450 odd lb/ft trying to put itself to the road in 1st gear of your average 2.08v with F16.
Oddball where exactly is this bearing in the main casing itself or on the part that can be removed with the whole gear set by unbolting the end case. I don't suppose you can show me on a diagram.
is this a load of rubbish ? seems it , i keep seeing people post saying the f20 is a stronger box is this true ? if it is why did vaux replace it for the f18 ... some late c20xe's were fitted with f18's iirc so they must be upto the job.
reason i ask is im after a new box and was going to go for the f18cr but seeing posts saying the f20 is better has put me off the f18 a bit hence ive been looking for a low mileage f20 any gen from you brainy miggers would be great cheers
edit: just remembered people fit f16's to 20xe's with 190Nm+? as standard so my guess would be its lb.ft and not Nm
eg: f16 160 lb.ft f18 180 lb.ft f20 200 lb.ft am i right ?
hence i could fit a f16cr to my 185Nm ecotec with 136 lb.ft and be fine
sorry oddball it must really pi** you off having to keep re answer posts youve allready answered, ive read this thread again and most of my questions are pretty much answered in one way or another. what i dont understand tho is why vaux went from the f20 to the f18 why not just stick to the f20 on the 16v range , is there a valid reason for this change ?
if the f18's and f20's use the same diff then why when i tried to fit an f20 gearpack into my f18 bell housing, it wouldnt go in because of the diff? ( had to put the f18 pack back in till can change the diff for the f20 one?.)
also a veccy f18 diff and a cav f18 diff are also different.
im running a cav f18 gearbox setup in my veccy bell housing at the moment. want to change to f20 because the ratio's to me feel crap and the box is fubbared
Gareth Before you tried to put the new cluster in did you see if it had the same number of teeth on the pinion cog that mates to the diff. Maybe it had a different diff ratio.
Oddball any chance of clarifying which bearing is different. I am planning on taking mine apart tomorrow and it would be very helpful if I new exactly which bearing you were refering to.
Oddball any chance of clarifying which bearing is different. I am planning on taking mine apart tomorrow and it would be very helpful if I new exactly which bearing you were refering to.
Tomorrow should be well interesting. Luckily I can do it at a friends garage so it will be up on a ramp and he has stripped the clusters down in the past so hopefully the car will be much better to drive. Well thats the plan. Also I will be able to put the new clutch in aswell.
Rating gearbox loads isn't very exact. The F number is just a generic part number. Sure, the bigger numbers go with bigger engines, but that's about it really.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Vauxhall Owners Forum
4.7M posts
72.7K members
Since 2000
A forum community dedicated to Vauxhall owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, reliability, maintenance, and more!