Q: Transmission slips while going downhill, when braking or coasting

asked by on August 25, 2016

I've been having some shifting issues when driving downhill. No problems occur when the road is flat, nor when the vehicle is under load. So, if I'm coasting or applying the brake at 60mph on average, the transmission starts slipping. I'm not able to get it back into gear if I start to slow down in this situation. The only way to put it in gear again is while I'm accelerating. Then it would go back into gear and I would continue driving as usual. I have checked the transmission fluid, which looks fine and is at a proper level. What could be the problem?

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Hello there, issues shifting when going downhill is a bit unusual for the 1998 K2500. There are a few possible causes for the transmission to slip when going downhill. The likely would be that the transmission fluid level is low, transmission linkage, or a mechanical fault. The first thing any technician will check as part of the diagnosis is the transmission fluid as you have done. The transmission fluid can move around and cause slipping on inclines, though the slip usually occurs when turning corners. If you need further help, a qualified technician, such as one from YourMechanic, will be able to diagnose this slip and perform any repairs required.

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