How to remove and install Piston ring and piston/connecting rod assemblies on BMW 325i?

Before removing the piston/connecting rod assemblies, check for rings at the maximum travel limit of the ring and remove those rings when necessary. Flip on the engine so that its crankshaft faces upwards. Use feeler gauges to check the connecting rod endplay and get a service limit from an automotive machine shop. Find out whether identification marks are present on the connecting rods and caps then mark them if they are not available. Loosen all connecting rod cap bolts and remove each cap and bearing insert. Drive each connecting rod/piston assembly through the top of the engine. Repeat this process for other cylinders too. Reassemble the connecting rod caps and bearing inserts in their respective connecting rods after removal. Check these new piston rings before they are installed to make sure their ends meet, adjusting them as required otherwise. Proceed to put rings onto pistons according to correct order only; then install pistons/rods assemblies after cleaning cylinder walls with chamfered upper edge in each bore and ensuring that a crankshaft is in place. Clean up bearing surfaces of both connecting rod big-end bore/cap and fit new upper bearing insert thereon. Lower bearing insert should be fitted into rod cap while making sure that piston ring gaps were located 120 degrees apart around its perimeter for proper positioning on piston top assembly along with lubricating it using clean engine oil before compressing them by inserting suitable piston ring compressor over until such point when all projections have been pressed down with enough force just like back into cylinder block holes provided by manufacturer themselves requiring rotation of crankshaft then later applying oil on cylinder walls followed by gentle installation of piston/rod assembly right inside cylinder bore guiding connection rods towards journal part of crankshaft itself ending up with checking connection bearings oil clearance applied Plastigage to be removed afterward in case it was not within range: keep supporting elements clear off any dust or contaminants since it has been already greased either way slid again onto initial position over journal, put rod back then tight those nuts repeated rest cylinders as well turning crank test binding on play.

Genuine BMW 325i Piston

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22 Pistons found

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BMW 325i Mahle Piston
Part Number: 11257558528
$334.92 MSRP: $398.26
You Save: $63.34 (16%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2006 BMW 325i | Sedan(E90)
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BMW 325i Mahle Piston
Part Number: 11251703456
$318.13 MSRP: $373.11
You Save: $54.98 (15%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Piston
- Replaces: 11-25-1-748-460, 11-25-1-738-717
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Convertible(E36), Sedan(E36)
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BMW 325i Mahle Piston
Part Number: 11257512526
$330.91 MSRP: $388.10
You Save: $57.19 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2001-2005 BMW 325i | Sedan M54 Engine(E46), Sedan(E46), Wagon M54 Engine(E46), Wagon(E46)
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BMW 325i Mahle Piston
Part Number: 11257512528
$334.55 MSRP: $392.37
You Save: $57.82 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Replaces: 11-25-7-509-177, 11-25-7-504-769
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2001-2005 BMW 325i | Sedan M54 Engine(E46), Sedan(E46), Wagon M54 Engine(E46), Wagon(E46)
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BMW 325i Mahle Piston
Part Number: 11257516062
$255.41 MSRP: $358.48
You Save: $103.07 (29%)
Ships in 1-3 Business Days
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Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2003-2005 BMW 325i | Sedan M56 Engine(E46), Wagon M56 Engine(E46)
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BMW 325i Mahle Piston
Part Number: 11257536373
$305.51 MSRP: $396.32
You Save: $90.81 (23%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2006 BMW 325i | Sedan(E90)
View related parts
BMW 325i Mahle Piston
Part Number: 11257516061
$263.44 MSRP: $308.97
You Save: $45.53 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2003-2005 BMW 325i | Sedan M56 Engine(E46), Wagon M56 Engine(E46)
View related parts
BMW 325i Mahle Piston
Part Number: 11251703457
$318.13 MSRP: $373.11
You Save: $54.98 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Replaces: 11-25-1-748-461, 11-25-1-738-718
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Convertible(E36), Sedan(E36)
View related parts
BMW 325i Mahle Piston
Part Number: 11251703461
$428.29 MSRP: $502.32
You Save: $74.03 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Replaces: 11-25-1-748-463, 11-25-1-738-720
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Convertible(E36), Sedan(E36)
View related parts
BMW 325i Mahle Piston
Part Number: 11251703460
$428.29 MSRP: $502.32
You Save: $74.03 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Replaces: 11-25-1-738-719, 11-25-1-748-462
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Convertible(E36), Sedan(E36)
View related parts
BMW 325i Mahle Piston
Part Number: 11251714807
$207.61 MSRP: $275.38
You Save: $67.77 (25%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1987-1992 BMW 325i | Convertible(E30), Coupe(E30), Sedan(E30)
View related parts
BMW 325i Mahle Piston
Part Number: 11251735758
$211.85 MSRP: $281.00
You Save: $69.15 (25%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1987-1992 BMW 325i | Convertible(E30), Coupe(E30), Sedan(E30)
View related parts
BMW 325i Mahle Piston
Part Number: 11251714809
$218.77 MSRP: $290.17
You Save: $71.40 (25%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1987-1992 BMW 325i | Convertible(E30), Coupe(E30), Sedan(E30)
View related parts
BMW 325i Mahle Piston
Part Number: 11251714808
$265.17 MSRP: $311.00
You Save: $45.83 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1987-1992 BMW 325i | Convertible(E30), Coupe(E30), Sedan(E30)
View related parts
BMW 325i Piston
Part Number: 11251722500
$318.13 MSRP: $373.11
You Save: $54.98 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Sedan(E36)
View related parts
BMW 325i Piston
Part Number: 11251722499
$318.13 MSRP: $373.11
You Save: $54.98 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Sedan(E36)
View related parts
BMW 325i Piston
Part Number: 11251722497
$318.13 MSRP: $373.11
You Save: $54.98 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Sedan(E36)
View related parts
BMW 325i Mahle Piston
Part Number: 11251735755
$330.91 MSRP: $388.10
You Save: $57.19 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Replaces: 11-25-1-726-417
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1987-1992 BMW 325i | Convertible(E30), Coupe(E30), Sedan(E30)
View related parts
BMW 325i Mahle Piston
Part Number: 11251722492
$330.91 MSRP: $388.10
You Save: $57.19 (15%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Piston
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Sedan(E36)
View related parts
BMW 325i Piston
Part Number: 11251748378
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 1992-1995 BMW 325i | Convertible(E36), Sedan(E36)

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1-20 of 22 Results

BMW 325i Piston

BMW 325i Piston turns blazing combustion into smooth wheel turning. The engine's moveable heart is the Piston, turning expanding explosive gases into crankshaft spin. In all BMW 325i, the Piston works in conjunction with the rings that seal it to the cylinder wall and connect rods that transmit its direct line thrust to the turning crank. Factory units are based on lightweight cast or forged aluminum alloy, but even the stock Piston remains strong thanks to precision machining and coatings to reduce scuffing and reflect heat. Bore diameter, compression ratio, and valve clearance are applied as guidelines for selection, and many pin bores accept floating pins held in position by clips for easy service. Through the years, two major styles of design have been applied for the BMW 325i to meet the needs of the crowd: a standard cast design optimal suited for daily driving and a forged variation for higher output builds where extra silicon or billet structure battles extreme pressure. Casting provides affordability with decent strength, while forging provides tighter grain, reduced weight, and higher durability, being the major distinguishing factor between the two Piston options. No matter what type, all BMW 325i engines rely on their Piston to stand against soaring temperatures with thinner rings coated to reduce friction and tighten up sealing to rev up faster.

If you are looking for OEM BMW 325i Piston, we highly recommend to shop with us. Not only do we offer budget friendly prices, but we also provide fast delivery. In addition, we have a hassle-free return policy on all genuine BMW 325i Piston that come backed by the manufacturer's warranty.

BMW 325i Piston Parts Questions & Experts Answers

Mahle Piston
11257536373
Q:
How to remove and install Piston ring and piston/connecting rod assemblies on BMW 325i?
Posted by Rayduan S.
A:
Before removing the piston/connecting rod assemblies, check for rings at the maximum travel limit of the ring and remove those rings when necessary. Flip on the engine so that its Crankshaft faces upwards. Use feeler gauges to check the connecting rod endplay and get a service limit from an automotive machine shop. Find out whether identification marks are present on the connecting rods and caps then mark them if they are not available. Loosen all connecting rod cap bolts and remove each cap and bearing insert. Drive each connecting rod/piston assembly through the top of the engine. Repeat this process for other cylinders too. Reassemble the connecting rod caps and bearing inserts in their respective connecting rods after removal. Check these new piston rings before they are installed to make sure their ends meet, adjusting them as required otherwise. Proceed to put rings onto pistons according to correct order only; then install pistons/rods assemblies after cleaning cylinder walls with chamfered upper edge in each bore and ensuring that a crankshaft is in place. Clean up bearing surfaces of both connecting rod big-end bore/cap and fit new upper bearing insert thereon. Lower bearing insert should be fitted into rod cap while making sure that piston ring gaps were located 120 degrees apart around its perimeter for proper positioning on piston top assembly along with lubricating it using clean engine oil before compressing them by inserting suitable piston ring compressor over until such point when all projections have been pressed down with enough force just like back into cylinder block holes provided by manufacturer themselves requiring rotation of crankshaft then later applying oil on cylinder walls followed by gentle installation of piston/rod assembly right inside cylinder bore guiding connection rods towards journal part of crankshaft itself ending up with checking connection bearings oil clearance applied Plastigage to be removed afterward in case it was not within range: keep supporting elements clear off any dust or contaminants since it has been already greased either way slid again onto initial position over journal, put rod back then tight those nuts repeated rest cylinders as well turning crank test binding on play.
Answered by BMW Parts Specialist Blaine / Aug 22, 2025