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SYNCHRO HUB 3RD/4TH
NOT AVAILABLE This part is no longer available
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Hub assembly 3rd gear TR6
Third gear hub assemblies fitted to 4 synchro boxes up to CC/CP TR6 are part numbered 509649, and later cars CR/CF TR6 part number 153844 which as far as we know were fitted from sometime in 1973 onward so only J type TR gearboxes will have them. This is an assembly of an inner static part and outer sliding part. The first part number has been No Longer Available (NLA) for many years and the 2nd part number has been out of stock for at least 3 years but we do have access to a very small number of these. Why is this important? Well, TR gearboxes have a propensity to fall out of 3rd gear on overrun which is a design fault prior to the later hub assembly being fitted. Not all gearboxes prior to 1973 have this problem but there is no way of knowing the problem will exist until the gearbox is installed in a car and tested. The cure is to fit the outer sleeve of hub part number 153844 which was the part modified to cure the problem. This part whilst not available from Triumph separately was remade some years ago as 153844X but that stock is now virtually gone. For the time being therefore it is not possible to fit one to every gearbox we rebuild so they are strictly rationed for fitment to those gearboxes that have a serious problem. We cannot at this time sell them individually either. We are however looking at having 153844X remanufactured but it is currently early days.