Bobcat's 200 and 300 series compact and mini excavators have been on North American sites for decades, and most of them are still working. This guide covers which models belong to which family, what fails on their travel circuit as the hours build, and how to identify the right final drive motor when one finally goes.
The Bobcat 220, 225 and 231 are the older compact machines in the range. Parts availability through dealers has thinned out, which is the usual reason owners of these machines end up looking for a replacement drive rather than a dealer repair.
The Bobcat 316, 319, 320, 321, 323 and 324 make up the small end of the 300 series, the machines bought for tight access work and utility trenching. The Bobcat 323 in particular remains one of the most common mini excavators in service.
Above them sit the Bobcat 325, Bobcat 328, Bobcat 331 and Bobcat 337G, along with the 329, 334, 335 and 341. These carry more weight and more hydraulic capacity, and their final drives work correspondingly harder.
For full published specifications, Bobcat's own documentation and the listings on Ritchie Specs and Machinery Trader are the sources to use.
Across the whole range, final drive failures follow the same pattern and the same three causes.
These machines work in trenches, and the drive sits at ground level. Once the duo-cone seal lets water in, the gear oil turns grey and the bearings have a few hundred hours left. Checking the oil at the plug takes two minutes and is covered in our final drive gear oil change guide.
An over-tight track loads the drive hub bearing continuously. On compact machines this is the single most common avoidable failure, and the measurements are in track tension and final drive damage.
A restricted or wrongly connected case drain line pressurises the motor casing and pushes the shaft seal out. See what a case drain filter does.
If one track is slow, weak or noisy, work through the symptoms of a failing final drive before ordering anything. Not every weak track is a failed drive.
There is no single figure, because the answer depends almost entirely on how the machine is looked after. A drive on a well maintained mini excavator, with gear oil changed on schedule and track tension set with a gauge, routinely outlasts the machine's second undercarriage. The same drive on a machine that has never had its oil checked can be finished inside two seasons. When owners tell us a drive failed early, the gear oil is grey in almost every case.
Both drives on a machine have done identical hours under identical conditions, so when one fails the other is usually not far behind. On the smaller 300 series machines the labour is much the same whether you do one side or two, which is why most owners replace the pair and keep the machine off the list of jobs for the next few years. On the larger Bobcat 337 and 341 class machines it is worth pulling the oil from the good side first and deciding on the evidence.
A slow track on a Bobcat mini excavator is not automatically a dead final drive. The two-speed solenoid, a restricted travel line, a tired main pump and a partially blocked case drain filter all produce the same complaint, and each costs a fraction of a drive. Pull the gear oil, check it for water and metal, and compare both tracks under load before ordering.
Model number alone will not identify the part. Bobcat used more than one travel motor specification within the same model designation depending on build year and undercarriage, so three details settle it: the casting number on the motor housing, the machine serial number, and a photograph of the mounting flange showing the bolt pattern and sprocket type. Send those to our parts specialist team and we will match them against the manufacturer parts books before anything ships.
Hydraulic America carries 159 new final drive motors under Bobcat final drive motors and a full range of main pumps under Bobcat hydraulic pumps. Shipping is by UPS across the contiguous United States and Canada, most in-stock units leave the same day, there is no core charge, and coverage runs up to two years, depending on the item, under our warranty policy.
Before the new drive goes on, flush the circuit if there was any metal in the old one, following the flush procedure, and torque the hardware to the figures on our bolt torque settings page. If you are weighing a repair against a replacement first, the numbers are in rebuild or replace a final drive motor.
