5th gear problems

Hi all,

My newly acquired cab keeps jumping out of 5th!! The problem only happens above 70mph but gets worse if I push her harder i.e get the gearbox oil nice and hot… I have read the other posts on the subject and assume that I need to blag a replacement box from somewhere?

If so how do I identify the right box for my car, are they stamped, if so where?

Cheers

David

First thing to do is to check your linkages are selecting the gear properly.

You can find the gearbox code on the underside of the gearbox stamped at the front of the bellhousing.

Thanks CQ, you really are mine of top info!!!! will check when it stop raining and I have more time…

Cheers

David

stop rigth there dotn drive any more i almost %100 know what this is and cheap and easy to do

mine did the same

Whats hapening is the 5th gear is beign starved of oil and at high speeds therefore temperatures the oils going thin

its the oil its old and thin or low

easy ?10 fix


firstly  buy a 17mm allen socket and 80/90w castrol transmission oilfrom halford

1)using a drip try drain old oil from car 17mm alen bolts under the box
2)replace 17mm sump plug
3)remove the spedo drive
4)remove 17mm end of gearbox plug
5)carefully refill with new gearbox oil 80/90w castrol until it comes out the end plug
6)replace end 17mm plus and spedo
7)all done

Hope this helps(btw check that oil numbers)

I think the standard oil is EP80 but semi synthetic GL5 75/90 is better. You need two litres and its usually sold in ? litre bottles so you?ll need ?..4. :wink:  Not sure where you can get it for ?10? :dontknow:

I?d be wary of removing the speedo cable, I?ve heard horror stories of the plastic cog dropping in the box. 8O

As gtimadman says drain the old oil (after a run to warm it up). As a check you can see measure how much comes out, if it is less than 2 litres that might be your problem. What I did when I recently changed the oil in my Caddy was jack it up on the passenger side and put in the 2 litres via the refill/level hole. Then you know that there really is two litres in there.

If a lot less than two litres comes out you need to find the leak. The green end cap fills with mud thrown up by the wheel and can rust through or one of the 3 seals (1x input shaft, 2 x drive shaft) can leak. On a 1300 Driver I had the bell housing/box joint leaked and unfortunately some of the loose bolts were inside the bell housing meaning I had to remove the box? to nip up the bolts.

Thanks guys, will check… I have receipts here from the previous owner, he had the seals done last year? perhaps the wrong grade of oil was used to refill? clutching at straws??????

David

Twin said

Thanks guys, will check… I have receipts here from the previous owner, he had the seals done last year? perhaps the wrong grade of oil was used to refill? clutching at straws??????

David

id be going with low oil level.

as said by the guys above,5th sits highest in the box so suffers first.

rather than just check it,change it for fresh for piece of mind.

neil.

Will do….may be some time though, I am talkling the nasty cosmetic stuff first, I have a feeling that once I start I may not stop!!! Vehicle is of road at present. I just want to get it looking good for the summer and then do a proper resto this winter, not sure it will turn out like that though, everywhere I look the rust worm is doing its evil work.


Cheers

David

mate the oil change can easily be doen in  half hour and you dont even need to jack the car up!

Jack it up - it will guarantee you reach overflow condition.

Regards
Rajan

Thanks for the info guys…. Like I say my priority has to be to get this badboy weatherproof and looking presentable before I start on the rest…

The mechanical side of things doesn't really hold any fear for me but sorting the bodywork is turning into a steep learning curve..

Thanks again guys

David

Hi all,

Well I finally got around to checking the oil in my box and it looks like you were right. I only managed to get 1/2 a litre from the drain plug under the diff and nothing from the plug near the end cap.

I have refilled with 2 litres of oil (is that the right amount?) so we will see how it goes if I finally get around to finishing the rest of the car…..

BTW I refilled through the reversing light switch hole as I have heard the horror sotries about the speedo drive dropping off….

Cheers

David