Dodge Nitro. Manual - part 121

threads do not contact the scale, the bolt must be replaced. See Fig. 211. 

Fig. 212: Ensuring Compression Ring Gaps Are Staggered 
Courtesy of CHRYSLER LLC 

3. Before installing pistons and connecting rod assemblies into the bore, ensure that compression ring gaps 

are staggered so that neither is in line with oil ring rail gap. See Fig. 212. 

1 - SIDE RAIL UPPER
2 - NO. 1 RING GAP
3 - PISTON PIN
4 - SIDE RAIL LOWER
5 - NO. 2 RING GAP AND SPACER EXPANDER GAP

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

Fig. 213: Identifying Piston & Connecting Rod
Courtesy of CHRYSLER LLC 

4. Immerse the piston head and rings in clean engine oil, slide the ring compressor over the piston and 

tighten with the special wrench. See Fig. 213. Ensure position of rings does not change during this 
operation.  

5. Install connecting rod bolt protectors, special tool # 8189. See Fig. 213.  

6. Rotate crankshaft so that the connecting rod journal is on the center of the cylinder bore. Insert the rod 

and piston into cylinder bore and guide the rod over the crankshaft journal. 

CAUTION: Do Not interchange piston assemblies cylinder-to-cylinder or bank-

to-bank.

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro

  

Fig. 214: Piston Orientation 
Courtesy of CHRYSLER LLC 

7. The arrow on top of piston must be pointing toward front of engine. See Fig. 214 

1 - ARROW FACES FRONT OF ENGINE

 

2007 Dodge Nitro R/T 

2007 ENGINE 4.0L - Service Information - Nitro