I agree with Dan, they most likley are electric. 1996 is not that old.
There are a few ways to tell for sure if you can view the TT. Don't know if your thinking of buying it or already have it.
If you can view it, one sure way if to get down and look behind the wheels at the brakes plate. This is the plate that looks like this.
See the wires going in the back of the brake plate. That is an electric brake.
If it is surdge system those wires will have a rubber hose that goes into the top area of the brake plate to get to the hydraulic wheel cylinder. No wires at all.
There are other ways to tell too. The surge brake trailers have a special large ball coupler. Behind the ball coupler is a master cylinder (hydraulic pump) The steel tubing runs from this box on the ball coupler back to the wheel where it then goes to the hose to jump to the wheel plate.
The connector that plugs into the truck, on Electric brakes it is a larger round 7 wire plug with 6 connectors in a circle and one fat pin in the center making the 7th pin
On surge brakes, unless you have a real oldy, it is a 4 wire flat connector. There use to be small round 4 wire plugs but again it only had 4 pins in the end of it not 7.
Good luck and hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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