8HP70 Tcc Solenoid, new and ready to install. Fits the 8HP70. Ships fast from the USA.
A shudder at steady highway speed that feels like driving over rumble strips, RPM that creeps up at cruise, or a converter clutch code is what sends most 8HP70 owners looking for a TCC solenoid. On this transmission the lockup solenoid is not sold or serviced as a stand-alone item by ZF, so what you receive here is the genuine ZF solenoid kit 1087 298 388, new in the ZF carton shown in the photo. The converter clutch solenoid is one of the pieces in that box, along with the line pressure solenoid and the regulators for each clutch and brake. Shops usually renew the whole set together, because the solenoids share the same fluid and the same miles.
The 8HP70 locks its torque converter very early, often in second gear, and modulates the lockup clutch with controlled slip instead of simply snapping it on. That job belongs to a variable-force pressure regulator in position B of the valve body. Sonnax's identification chart calls it EDS-2 on BMW units, SOL TCC on the Chrysler-family 8HP70 and 845RE, and EPC-TCC N371 on Audi versions. The transmission module varies its current to set exactly how hard the converter clutch is applied. When the regulator sticks, leaks internally or its inlet screen clogs, the clutch cannot hold the commanded slip, so it chatters, slips at cruise or never fully applies.
Not every shudder is the solenoid. Worn fluid, a leaking mechatronic connector sleeve and wear in the valve body circuits that feed the converter clutch all produce the same feel.
Check the fluid level hot and its condition first; old LifeguardFluid can cause lockup chatter on its own. Look for oil at the connector sleeve. Read codes with a tool that reaches the transmission module and, if possible, watch commanded versus actual converter slip at cruise. With the mechatronic out, bench test the B position regulator with the circuit board removed; Sonnax's ZF8-ZIP booklet calls for about 5.0 ohms at 20 C using a meter that tests under 0.6 volts. TransGo's SK8HP repair kit, covered in Gears Magazine, targets converter clutch codes caused by valve body wear on these first-generation units, so a perfect solenoid reading points you toward the valve body. Our ZF8HP solenoid guide and Grand Cherokee problems guide walk through both.
ZF kit 1087 298 388 is listed for the first-generation 8HP45 and 8HP70, which covers BMW, Jaguar, Land Rover and Rolls-Royce applications, the 2014-and-later Jeep Grand Cherokee and the 2015-2023 Dodge Charger, Challenger and Durango. It does not fit second-generation units such as the 8HP75 or 850RE. Ram 1500 owners should confirm which generation their truck uses before ordering. Compare the cap colors and connectors in the photo with the solenoids on your valve body, or send us your year and VIN. Browse the ZF 8HP collection for everything else that fits.
Drain the fluid, drop the pan and unplug the connector sleeve to lower the mechatronic unit. Change one regulator at a time so each returns to its own bore, inspecting the TCC bore and the others for scoring as you go. Fit new O-rings wet with fluid and torque the retaining plates evenly. Replace the sleeve and the pan with its integral filter while you are in there; a pan, filter and ATF kit for Ram, Jeep and Dodge covers that. Refill with ZF LifeguardFluid 8 and set the level at temperature. Clear codes, reset adaptations, then drive several lockup cycles at steady speed so the module relearns converter slip. If the shudder returns, look at the valve body or a full 8HP70 overhaul kit.
| Fits | 8HP70 |
| Part type | Tcc Solenoid |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. It is the genuine ZF solenoid kit 1087 298 388 shown in the photo. The converter clutch solenoid is included with the line pressure and clutch regulators, which is how ZF supplies them.
Position B on the valve body. Sonnax labels it EDS-2 on BMW, SOL TCC on the Chrysler-family 8HP70 and 845RE, and EPC-TCC N371 on Audi units.
It will if the TCC regulator is the cause. Check fluid condition, the connector sleeve and the bench resistance first, since worn fluid and valve body wear cause the same shudder.
The kit is listed for the 2015-2023 Charger, Challenger and Durango and the 2014-and-later Grand Cherokee with first-generation ZF eight-speeds. Send your VIN if you are not sure.
Yes. Reset the transmission adaptations with a scan tool, then drive through all gears and several steady-speed lockup cycles so the module relearns converter slip and clutch fill.
