lm7, and lm4 whats the dif?

[JeRM82]

On the OEM spec's page of the website I saw that there was an LM7 and an LM4 listed. The LM4 was only listed under 2003......whats the dif on these motors....is the lm4 an "updated version of the LM7, like the LS2 is to the LS1? Or is it a TYPO?

[ONE04FX4]

lm7==5.3L

lm4==4.8L

[JeRM82]

someone might want to change that in the HP listings cause it says the LM4 is a 5.3......

[PewterC3]

The LR4 is the 4.8.

The 5.3 is known by many names:

Vortec 5300 5.3L V-8 (LM7/LM4/L59)
Vortec 5300 Gen IV V8 ( LH6 )
Vortec 5300 V-8 (L33)
An all-aluminum version of the Vortec 5300 V-8 (L33) engine is available in Chevrolet 1500 Silverado Extended Cab and GMC Sierra Extended Cab models equipped with four-wheel drive and the short box. The 5.3L V-8 produces 310 hp (231 kw) and 330 lb.-ft. (447 Nm) of torque.

Constructed with an aluminum block and cylinder heads, this version of the Vortec 5300 V-8 is 100 pounds (45.4 kg) lighter than versions with an iron block. Reduced mass enhances handling and balance, as well as fuel economy.