Far East Reliability

 "September 29th, 1945

The following technical defects were discovered in tanks and SPGs of the Transbaikal Front after crossing the Manchurian and Mongolian steppe, mountains of the Greater Khingan, and the heavily swamped region until Changchung and Mukden.

1. Widespread cases of melting battery seals on T-34 tanks and SU-100 SPGs.
   Due to the low quality of seals (low melting temperature) and lack of asbestos packing cords, the seals melted, seeped into battery cells, and covered the upper parts of the plates. Refurbishment of batteries was successfully carried out by brigade and regiment level repair units.
2. Widespread cases of destruction of M4A2 road wheel tires.
   Destruction happened chiefly due to poor vulcanization of the rubber and especially difficult road conditions (high ambient temperature and sand-stone terrain).
3. There were cases of broken T-34 and SU-100 clutch mechanisms due to destruction of inner ball bearing #226, breaking of packing rings, and heightened wear of the grooves on the mobile and immobile engagement cups.
   These incidents are caused by a lack of timely lubrication and the use of solid lubricating grease instead of konstalin. At temperatures of over 75 degrees solid lubricating grease liquifies and leaks out, which results in insufficient amounts of lubrication in the clutch and premature wear.

In addition to the aforementioned defects, the following were encountered.

Type of defect	T-34 and SU-100		M4A2
	Amount	Percent of total	Amount	Percent of total
Engine damage	30	57	8	53.4
Gearbox gear damage	8	15.1	-	-
Main clutch damage	2	3.7	2	13.3
Final drive clutch damage	4	7.4	-	-
Final drive damage	5	9.4	3	13.3
Fan turbine damage	4	7.4	-	-
Driveshaft damage	-	-	3	20
Total	53	100	15	100

Damage to T-34 and SU-100 engines was due to following reasons:

• 14 engines expended their warranty period and were replaced.
• 8 cases of the distribution mechanism breaking due to manufacturing defects.
• 4 cases of the engine overheating due to the driver's fault.
• 4 cases of cracks in the lower casing due to manufacturing defects.

The biggest drawback in the use of tanks and SPGs is a lack of timely lubrication and oil changes. Routine maintenance schedules were upset due to a lack of necessary types of lubricants, especially as the armoured vehicles were assembling.

In total, 8.3% of T-34 and SU-100 vehicles and 8.2% of M4A2 tanks broke down during the operation. 

All tanks and SPGs worked at 90-100 degrees in the steppe and Greater Khingan mountains, which required constant vigilance from their drivers.

A brief analysis of technical defects of T-34, SU-100, and M4A2 tanks shows that these tanks are appropriate for operating in semi-desert and mountainous conditions of the Far East.

Assistant to the Chief of the 1st Department of the GBTU Vehicle Usage Directorate, Guards Engineer-Major Kotov"

CAMD RF F.38 Op.11362 D.147 L.71-73

Printed in Glavnoye Bronetankovoye Upravleniye Lyudi, Sobytiya, Fakty v dokumentakh, 1944-1945 p.698