Shift Pointers
- Author: Pete Luban, ATSG Technical Supervisor
This month’s problem/fix comes to us from overseas and concerns the ZF 5-HP-24 transmission. Although this problem has occurred primarily in Jaguars in this shop, it also could occur in other makes using this transmission.
Here is how the symptoms were described to me: The car comes in with a complaint of harsh upshifts and downshifts, no codes are stored, and the transmission is not in limp mode.
It would appear as if the TCM defaulted to high line pressure, only with no other default actions.
Figures 1 and 2 illustrate the nature of the problem: The E-clutch feed pipe has a hole worn into it from contact with the valve body (see Figure 3).
The only thing I can figure is that the valve body covers enough of the hole that it minimizes the leak, preventing default actions such as limp mode or storage of a gear-ratio-error code.
Figure 4 shows the repair of the tube. The damaged area of the feed pipe was cut out, and a sleeve was installed and soldered in place to rejoin the pipe.
Figure 5 shows how the pipe was secured to the rib in the case to prevent further contact with the valve body. It seems to me that some of the raised area of the valve body in the contact area also could be removed to help alleviate this problem. It is also important to ensure that the feed tube fits into the feed hole snugly and that the hold-down bracket that secures the feed pipe in place is installed.
Getting automotive parts overseas often is expensive and difficult, which is why this shop chose to repair the feed pipe rather than try to acquire a new one, and a nice piece of work it is. However, here in the States we have access to ZF parts distributors, which should make acquiring this feed pipe not too difficult. The ZF part number for the E-clutch feed pipe is 1058301021. Remember, this is not a Jaguar or BMW part number; it is a ZF part number.
Many thanks to Bart Schillings of Bart Transmission & Turbo Shop in Heerlen, The Netherlands, for the info and pictures.
