The formal language for Chinese people in Malaysia of course is Mandarin language, known as Huayu (华语).
But there are a few dialects that still be spoke by the Chinese people in Malaysia.
Hokkien is the most dialect spoken in Malaysia. The Malaysian Hokkien are divided into two localised dialects; the Penang Hokkien (northern) comprising Kedah, Penang, Perak and Perlis and Southern Peninsular Hokkien in Johor, Malacca and neighbouring Singapore. The northern Hokkien contains more Malay loanwords than the southern with the latter maintaining more of their original Hokkien words.
The Malaysian Cantonese became the contact language in the Malaysia’s capital of Kuala Lumpur with a distinct phonology and grammar from standard Cantonese spoken in Pearl River Delta region of China including in Hong Kong and Macau.
Other dialects such as Hakka, Foochow, Chaozhou (Teochew people), and Hainan are rarely be heard nowadays.
Chinese language also has been taken as loanwords in Malay language.
Differences Between Chinese Dialects In Malaysia
In Malaysia the major language and dialects that speak by Chinese are Mandarin, Hokkien and Cantonese. Among the three languages or dialects, Mandarin is widely use around the world. While Cantonese and Hokkien are using in the certain places and families.
Each of the dialects are quite difference with the other. Sometimes people just assume that they are perfectly different languages.
Class of Mandarin 