Specs, fluids & service · 1975–1993
Mercedes-Benz Unimog U1300L (435) specs, fluids and service intervals
The numbers you need in the garage, on one page: spec sheet, capacities and service intervals, wheels and tires, and the parts to order. Sourced from owners, specialists and the factory; tags marked confirm in manual haven't been checked against a factory source yet.
Spec sheet
| SERIES | Unimog 435 · U 1300 L = 435.115 |
|---|---|
| BUILT | Gaggenau, Germany · 1975–1993 |
| PRODUCTION | 30,726 (435 series) · 21,775 U 1300 L |
| MILITARY NAME | Lkw 2 t tmil gl (Bundeswehr, from 1978) |
| ENGINE | OM 352 5,675 cc I6 diesel, 96 kW / 363 N·m · OM 366 from 1987 |
| GEARBOX | 8-speed synchromesh, double reduction · 0.15–80 km/h |
| DRIVE | Part-time 4WD, front and rear locking diffs |
| AXLES | Portal axles, coil springs |
| BRAKES | Air-over-hydraulic dual-circuit discs |
| WHEELBASE | 3,250 mm (L/37: 3,700 mm) |
| GROUND CLEARANCE | 440 mm (17.3 in) |
| FORDING | 1,200 mm (47 in) |
By year
| YEARS | PLATFORM | ENGINE | OUTPUT | NOTES |
|---|---|---|---|---|
| 1975–1993 | U 1300 L · 435.115 | OM 352 5.7 I6 diesel, naturally aspirated (catalogued as OM 353) | 96 kW (130–131 PS) / 363 N·m | 3,250 mm wheelbase. 21,775 built, including 473 RW1 fire trucks. The Bundeswehr Lkw 2 t tmil gl. |
| 1975–1993 | U 1300 L · uprated engines | OM 352 / OM 353 family, including turbo OM 352A | 110 / 115 / 124 kW | Wikipedia's variant table lists these outputs for 435.115. The turbo engines use different injector nozzles. |
| 1987–1993 | U 1300 L · OM 366 | OM 366 / OM 366A 6.0 I6 diesel | confirm in manual | The OM 366 replaced the older engine from 1987. Ex-Bundeswehr trucks on BaT include 6.0 turbodiesels. |
| 1975–1993 | U 1300 L/37 · 435.117 | OM 352 / OM 353 | 96 / 110 / 124 kW | 3,700 mm wheelbase; 779 built |
| 1975–1993 | U 1700 / U 1700 L · 435.110 / .111 | OM 353.961 A turbo, no intercooler | 124 kW (169 PS) / 520 N·m | Up to 5 t payload. 1,161 U 1700 and 808 U 1700 L built, on 10-lug axles. |
| 1975–1993 | U 1700 L/38 · 435.113 | OM 352 / OM 353 turbo | 110 / 124 kW | 3,850 mm wheelbase; 5,898 built |
| 1975–1993 | Thyssen TM 170 / TM 215 · 435.160 / .161 | OM 353 / OM 366 | 124 / 157 kW | Armored personnel carriers on the 435 chassis: 290 TM 170 and 15 TM 215 |
Fluids, capacities & service intervals
Most 435s in the US have spent years in a German army depot and then a container. Expect old fluids, aged tires and seals that have sat dry. Get the operator's manual for your engine first; Mercedes printed it in English. Then change every fluid before you drive it far, as one owner did before a 1,650 km trip home.
| ITEM | SPEC / CAPACITY | INTERVAL | NOTES & PARTS |
|---|---|---|---|
| Engine oil & filter | Diesel engine oil to the operator's manual · capacity confirm in manual | Then at the manual's interval; owners drain the portals at the same time (about every 8,000 km) | Expedition Imports lists MANN filter 3661800809 for 435.115 U 1300 Ls with OM 353.961 (1978–1989) and OM 353.959 (from 1987). Check your filter housing before ordering.Oil filter 3661800809 (MANN) · Expedition Imports ↗ |
| Portal hub oil (×4) | GL-5 hypoid gear oil, 75W-90 synthetic to MB sheet 235.8 suggested · about 300 ml per portal (≈ 1.2 L total) | Every engine oil change | Check all four for metal on the plug and compare the levels; a low hub plus an overfull diff points to breather pumping. Some owners also log hub temperatures.Lower outer portal seal, 140 mm (carry a spare) · Expedition Imports ↗ |
| Front & rear differentials | GL-5 gear oil (Mobil lists 75W-90 synthetic or 80W-90) · about 2.5 L each in Mobil's Unimog table | Drain and refill on purchase, then per the manual | An overfull diff means a portal is pumping oil into it.Differential seals and parts, Unimog · Expedition Imports ↗ |
| Transmission | Civilian: synthetic 75W-85 GL-4 to MB sheet 235.4 · Ex-Bundeswehr (BW 435): MB sheet 231.3 calls for 10W engine oil | Drain and refill on purchase | Use GL-4, not GL-5 (m37charlie, BITOG). Check which spec your manual and gearbox tag call for, because the military 435 gearbox is the exception. |
| Air dryer cartridge & tank drains | MANN desiccant canister | On purchase, then per the manual; drain the tanks regularly | Moisture in the air system shortens the life of locker, front-drive and brake valves.Desiccant air dryer canister (U1300L and others) · Expedition Imports ↗Air tank drain valve · Expedition Imports ↗ |
| Fuel filters & water separator | Replace the elements and pre-filter; drain the water | On purchase, then per the manual | Stored trucks collect water and sediment in the tank. One ex-army truck on BaT had its fuel tank reconditioned and its filter replaced.Fuel filter bowl, new style · Expedition Imports ↗Fuel pre-filter gasket · Expedition Imports ↗ |
| Air filter | Dry element (part number by engine; confirm in the parts manual) | On purchase; check often in dust | Owners in dusty country add a cyclone pre-cleaner to the snorkel (Hodakaguy, Expedition Portal).Air filter elements, Unimog · Expedition Imports ↗ |
| Coolant | MB-approved antifreeze · type and capacity confirm in manual | Flush on purchase | Check the water pump weep hole and hoses while it's drained.Water pump OM352 / U1300L · Expedition Imports ↗ |
| Power steering fluid & filter | Fluid to the manual · replace the reservoir filter | Expedition Imports suggests every 3–5 years on other Unimog series | Expedition Imports calls the steering filter the most overlooked filter on a Unimog. Confirm the 435's filter part number in the parts manual.Power steering filters, Unimog · Expedition Imports ↗ |
| Brake & clutch fluid | Brake fluid to the manual confirm in manual | Flush on purchase | The brakes and the clutch are hydraulic, operated by air; old fluid corrodes the master and slave cylinders.Clutch master cylinder, SBU · Expedition Imports ↗ |
| Chassis grease | Every nipple: kingpins, propshafts, pedal and gear linkages | Every service | Regular greasing and oil checks are most of the work, and they aren't difficult (Merv, HUBB). |
| Tires | Check the DOT date code and the load rating against your real weight | On purchase | One BaT seller flagged a truck's original Continentals for replacement because of age. Don't go small on load rating on a heavy camper.Continental MPT 81 365/80 R 20 · Expedition Imports ↗Continental MPT 81 335/80 R 20 (12.5R20) · Expedition Imports ↗ |
| Batteries & 24 V electrics | 24-volt system on military trucks | On purchase | Clean the grounds, load-test the batteries as a pair, and check the starter. A new Bosch 24 V starter costs about half as much as a Mercedes rebuilt unit, according to Expedition Imports.Starter 24 V (Bosch), U1300L and others · Expedition Imports ↗ |
Capability
| Payload | 1,500 kg (3,307 lb) Bundeswehr Lkw 2 t tmil gl rating; the U 1700 L carries up to 5 t (Mercedes-Benz) |
|---|---|
| Gross weight | 7,500 kg (16,535 lb) 7.5-tonne class |
| Towing | 1.5-tonne trailers or towed weapons up to 2.25 t Military tractor role |
| Curb weight | 4.5–5.5 t (9,900–12,100 lb) Wikipedia; the Bundeswehr lists 5,760 kg |
| Ground clearance | 440 mm (17.3 in) |
| Approach / departure | 46° / 51° |
| Wading depth | 1,200 mm (47 in) |
| Top speed | 80 km/h (50 mph) military; 80–110 km/h depending on gearing |
| Fuel economy | 17.5–19 L/100 km (≈ 12–13 mpg US) Wikipedia; owners report about 11 mpg and 20–30 L/100 km loaded |
| Range | 800 km (≈ 500 mi) Bundeswehr figure |
| Turning | 14.1 m (46 ft) Wikipedia lists this as the turning radius |
| Length / width / height | 5,500–6,100 / 2,300 / 2,875 mm Wikipedia; the Bundeswehr cargo truck is 5,800 × 2,430 × 3,170 mm |
Wheels & tires
| Factory tire | 20-in wheels on 6-lug disc-brake axles; 365/80R20 (14.5R20) Continental MPT 81 is common on ex-military trucks sold in the US · 335/80R20 (12.5R20) is the other common 20-in Unimog size |
|---|---|
| Bolt pattern | 6-lug (U1300); the U1700 uses 10-lug axles |
| Lug thread | M18 x 1.5 studs (6-lug disc-brake axles) |
| Biggest tire · Stock | 365/80R20 (≈ 42.9 in) |
| Biggest tire · Cab lift | 395/85R20 |
Common Unimog U1300L (435) repairs
- Replace portal hub seals and fix the breathersDIFFICULTY 3 / 5
- Rebuild a portal with new bearingsDIFFICULTY 4 / 5
- Replace disc brake padsDIFFICULTY 2 / 5
- Service the air dryer and drain the air tanksDIFFICULTY 1 / 5
- Replace the clutch master cylinderDIFFICULTY 3 / 5
- Replace the water pump (OM 352)DIFFICULTY 3 / 5
- Replace shock absorbersDIFFICULTY 2 / 5
- Replace a head gasket (OM 352 / OM 366)DIFFICULTY 4 / 5
Always confirm torque figures, fluids and capacities against the factory service manual for your VIN. See the disclaimer; some parts links are affiliate links.