Which do you prefer=timing chain or timing belt?

**sequoias** · 06-09-2009, 10:01 PM

I would like to bring up to debate about timing chain and belts. In my views, I prefer timing chain because of reliabity and less worrying about it breaking suddenly like the timing belt usually do if you negect the service schedule. The timing chain will make some noise which will tell you that it is time to replace it soon, while timing belt doesn't....it does that like a ticking time bomb which is silent surprise. Plus, I hate how many car companies design their engines which piston and valves are close to each other, if it breaks...they crash into each other and end up with a costly engine replacement.

I'm currently worrying about it breaking because I'm already at 90k miles and it needs to be serviced soon and it is pretty expensive which costs $395 for the 90k mile service, I can't afford that right now and hopefully will do that next month as I'm going to work 24 hours on Sat and Sunday this weekend and hopefully get more extra work later this month and next month.

Babyblue · 06-09-2009, 10:09 PM

I never had a timing belt, break on me.

I do not know if my current vehicle, have a timing chain or belt.

Milwaukee · 06-09-2009, 11:08 PM

I have replace timing belts on geo storm

I am supposed to change my timing belt on 94 geo tracker 5,000 more miles then I change.

new timing belt cost $25
tension pulley cost $50
water pump $40

That all what I need to do.

For me I rather have timing chain but geo doesn't came with that so it

deafsmogtech · 06-10-2009, 03:26 AM

Quote:

Originally Posted by sequoias

I would like to bring up to debate about timing chain and belts. In my views, I prefer timing chain because of reliabity and less worrying about it breaking suddenly like the timing belt usually do if you negect the service schedule. The timing chain will make some noise which will tell you that it is time to replace it soon, while timing belt doesn't....it does that like a ticking time bomb which is silent surprise. Plus, I hate how many car companies design their engines which piston and valves are close to each other, if it breaks...they crash into each other and end up with a costly engine replacement.

I'm currently worrying about it breaking because I'm already at 90k miles and it needs to be serviced soon and it is pretty expensive which costs $395 for the 90k mile service, I can't afford that right now and hopefully will do that next month as I'm going to work 24 hours on Sat and Sunday this weekend and hopefully get more extra work later this month and next month.

I like both rubber belts and chains. The rubber belts can be break due to overdue maintenance, or failure tensioner(s), idler(s) or water pump or oil/coolant saturated timing belt, can be engine interference, not all the vehicles. Example, Ford Probe or Mazda Protege w/2.0 or 2.2L ( I can't remmby which is 2.0L or 2.2L) is engine interference (valves hit pistons).
Belts are easy or hard to replace depend on the engine designs. Timing belt replacement is my favorite.
Chains never break, but noises (normal). They can be the worst noises sound like knocks or slaps that mean the chain(s) are loose due to worn out tensioner(s) or guides or chain(s) (some engines have low oil pressure that cause hydraulic tensioner collapsed). To fix loose chain(s) on V6 or V8 engines are expensive. I recently diagnosed a noise in the top of the engine
from a 2003 Suzuki Grand Vitara w/ 2.7L V6, asked my hearing tech pinpointed the right bank (passenger side), told me he think chain. I checked
TSB, says bad hydraulic tensioner. I turned this car over to my another tech to do tensioner replacement. The cost to fix the noise chain is $1,500. This Suzuki Grand Vitara was only 85k miles on it. I had been seen the Ford 5.4L V8 for tensioner and guide replacements. I rare work on the chain timings cuz of vast labor time that will not permitt me to do smog checks.
I feel that timing chain replacements in the OHV engines such as Chevy/Ford/Chrylser are cheaper than SOHC or DOHC. The chains in SOHC or DOHC engines are louder than OHV engines cuz the chain in OHV engine is small links. I dont like the timing chain driven in SOHC or DOHC engine in any domestic vehicles. My currently vehicles are the timing chain driven in OHV engines, however my old Alfa Romero use double roller timing chains in DOHC 4 cylinders. These discussion is based on my professional automotive mechanic (over 30yrs) in the repair shops. I'm not a Saturday mechanic. Hey don't get paranoid or worry about your car to be match my comment as above.

diehardbiker · 06-10-2009, 06:05 AM

I no want deal with timing belt. Have had timing chains on all my vehicles and have zero problem whatsover.

**sequoias** · 06-10-2009, 11:14 AM

I have heard of timing chains that can be very costly to repair if it becomes loose as the chain stretchens. That is much more expensive than belt driven engines. Belts rarely stretch while chains do sometimes. It varies on the design of the engines and the manufacturers.

Most Hondas are interference engines (which is why I'm worried), some Toyotas, etc. Chrysler is the only company that has avoided making interference designed engines.

Quote:

Originally Posted by deafsmogtech

I like both rubber belts and chains. The rubber belts can be break due to overdue maintenance, or failure tensioner(s), idler(s) or water pump or oil/coolant saturated timing belt, can be engine interference, not all the vehicles. Example, Ford Probe or Mazda Protege w/2.0 or 2.2L ( I can't remmby which is 2.0L or 2.2L) is engine interference (valves hit pistons).
Belts are easy or hard to replace depend on the engine designs. Timing belt replacement is my favorite.
Chains never break, but noises (normal). They can be the worst noises sound like knocks or slaps that mean the chain(s) are loose due to worn out tensioner(s) or guides or chain(s) (some engines have low oil pressure that cause hydraulic tensioner collapsed). To fix loose chain(s) on V6 or V8 engines are expensive. I recently diagnosed a noise in the top of the engine
from a 2003 Suzuki Grand Vitara w/ 2.7L V6, asked my hearing tech pinpointed the right bank (passenger side), told me he think chain. I checked
TSB, says bad hydraulic tensioner. I turned this car over to my another tech to do tensioner replacement. The cost to fix the noise chain is $1,500. This Suzuki Grand Vitara was only 85k miles on it. I had been seen the Ford 5.4L V8 for tensioner and guide replacements. I rare work on the chain timings cuz of vast labor time that will not permitt me to do smog checks.
I feel that timing chain replacements in the OHV engines such as Chevy/Ford/Chrylser are cheaper than SOHC or DOHC. The chains in SOHC or DOHC engines are louder than OHV engines cuz the chain in OHV engine is small links. I dont like the timing chain driven in SOHC or DOHC engine in any domestic vehicles. My currently vehicles are the timing chain driven in OHV engines, however my old Alfa Romero use double roller timing chains in DOHC 4 cylinders. These discussion is based on my professional automotive mechanic (over 30yrs) in the repair shops. I'm not a Saturday mechanic. Hey don't get paranoid or worry about your car to be match my comment as above.

**sequoias** · 06-10-2009, 11:18 AM

Quote:

Originally Posted by diehardbiker

I no want deal with timing belt. Have had timing chains on all my vehicles and have zero problem whatsover.

Are you aware of them becoming loose because deaf people can't hear that?

**sequoias** · 06-10-2009, 11:21 AM

Quote:

Originally Posted by Milwaukee

I have replace timing belts on geo storm

I am supposed to change my timing belt on 94 geo tracker 5,000 more miles then I change.

new timing belt cost $25
tension pulley cost $50
water pump $40

That all what I need to do.

For me I rather have timing chain but geo doesn't came with that so it

The parts are cheap, yes BUT labor...gotta remember that. It is pain in the ass to work on so I rather have someone do the work. I do not have special tools either and plus trying to get the crank pulley bolt loose is really tough, you need a impact wrench or a a powerful compression air wrench, depends.

Milwaukee · 06-10-2009, 11:51 AM

You go to Lowes or Harbor Frieght for cheap tools.

get those electric impact wrench IT WORTH. We have air impact wrench but I choose electric why no deal with air hose.

You get manual book that show how to do that.

That what I did when I replace timing belt on geo first time.

**sequoias** · 06-10-2009, 01:23 PM

Quote:

Originally Posted by Milwaukee

You go to Lowes or Harbor Frieght for cheap tools.

get those electric impact wrench IT WORTH. We have air impact wrench but I choose electric why no deal with air hose.

You get manual book that show how to do that.

That what I did when I replace timing belt on geo first time.

Is your engine transverse or that goes to the rear wheels layout? Well I have looked at pictures on how it's done. I'm not going to do that because it involves lifting the engine out of the engine bay, make sure timing is right, all that... I don't want to **** it up and prefer have shop do it.

Also, I do not want to waste money on tools that I would rarely use. No thanks.

**Foxrac** · 06-10-2009, 03:20 PM

I prefer timing chain, that what Chevy truck has timing chain with V8.

Timing chain is hardly need replace but I wish that engine need be designed for last longer without worry about need replace, I can learn to change the parts in car if I want too.

**Foxrac** · 06-10-2009, 03:22 PM

Quote:

Originally Posted by sequoias

Are you aware of them becoming loose because deaf people can't hear that?

I think deaf people can feel the bad noise from timing chain when loose so severely.

**sequoias** · 06-10-2009, 03:45 PM

Quote:

Originally Posted by Foxrac

I think deaf people can feel the bad noise from timing chain when loose so severely.

it would be safer if you heard it making slapping sounds.

purplecatty · 06-10-2009, 07:13 PM

I prefer Timing Chain. Even though I never had Timing Belt breaks on me. Currently, My Durango and Jeep uses Timing Chain. If Timing chain became stretched, I would replace that myself otherwise, either one would have been sold to another owner

1989 Mazda 323 use Timing Belt. I don't have issue with that but it's the space between right frame and engine where timing belt located. The water pump pulley was the toughest part and I had to use 10mm monkey wrench to loosen 4 bolts on pulley before I take covers off because it gave me only 1 inches clearance. Once the cover and Crankshaft pulley is off (crankshaft pulley was the easiest cuz it have 6 bolts holding main pulley and I loosen it first then use my power drill with 10mm socket on adapter to make job real quick).

It took me 30 min to do Timing belt replacement. I don't replace timing belt on Mazda often, I let it go way past it's timing belt service mile cuz if timing belt breaks, the engine won't get damaged cuz of piston and valve have its clearance whether it's open or close. Out of 225,000 miles on Mazda 323, I only replace twice.

Same goes for 1990 Mazda Protege, I only replaced once.

My 1967 Chevy C-10 Pickup truck had it's timing sprocket sheared off cuz it's nylon teeth on main crankshaft behind the cover. The shop that rebuilt the truck before they sold it to me use cheap timing sprocket. I decide not to bother replace timing sprocket. I simply replace engine cuz original engine was full of grease and oil and it's really dirty. I replaced it with 1977 Camaro modified engine (305 block with 350 head).

I rather have timing Chain than belt so I don't have to worry about belt service every 70k miles or whatever manual says. Plus, I'm just tired of fix fix fix fix engine (done that many times) and I just want to "retire" tho.

Catty

purplecatty · 06-10-2009, 07:16 PM

Quote:

Originally Posted by sequoias

I would like to bring up to debate about timing chain and belts. In my views, I prefer timing chain because of reliabity and less worrying about it breaking suddenly like the timing belt usually do if you negect the service schedule. The timing chain will make some noise which will tell you that it is time to replace it soon, while timing belt doesn't....it does that like a ticking time bomb which is silent surprise. Plus, I hate how many car companies design their engines which piston and valves are close to each other, if it breaks...they crash into each other and end up with a costly engine replacement.

I'm currently worrying about it breaking because I'm already at 90k miles and it needs to be serviced soon and it is pretty expensive which costs $395 for the 90k mile service, I can't afford that right now and hopefully will do that next month as I'm going to work 24 hours on Sat and Sunday this weekend and hopefully get more extra work later this month and next month.

Some V8 or V6 engine have special kit that do not require Belt or Chain, just gears between Crankshaft Timing sprocket and camshaft sprocket which is a modification or 3rd party item. Especially Chevrolet and Ford

Catty

**sequoias** · 06-10-2009, 09:09 PM

Quote:

Originally Posted by purplecatty

I prefer Timing Chain. Even though I never had Timing Belt breaks on me. Currently, My Durango and Jeep uses Timing Chain. If Timing chain became stretched, I would replace that myself otherwise, either one would have been sold to another owner

That's cool.

Quote:

1989 Mazda 323 use Timing Belt. I don't have issue with that but it's the space between right frame and engine where timing belt located. The water pump pulley was the toughest part and I had to use 10mm monkey wrench to loosen 4 bolts on pulley before I take covers off because it gave me only 1 inches clearance. Once the cover and Crankshaft pulley is off (crankshaft pulley was the easiest cuz it have 6 bolts holding main pulley and I loosen it first then use my power drill with 10mm socket on adapter to make job real quick).

Ohhh I didn't know you can use a drill with the socket adapter, that's neat tool for sure.

Quote:

It took me 30 min to do Timing belt replacement. I don't replace timing belt on Mazda often, I let it go way past it's timing belt service mile cuz if timing belt breaks, the engine won't get damaged cuz of piston and valve have its clearance whether it's open or close. Out of 225,000 miles on Mazda 323, I only replace twice.

How can you do that in 30 minute? I heard it takes about 4 hours to do that on a fwd car.

Quote:

My 1967 Chevy C-10 Pickup truck had it's timing sprocket sheared off cuz it's nylon teeth on main crankshaft behind the cover. The shop that rebuilt the truck before they sold it to me use cheap timing sprocket. I decide not to bother replace timing sprocket. I simply replace engine cuz original engine was full of grease and oil and it's really dirty. I replaced it with 1977 Camaro modified engine (305 block with 350 head).

That's not good there. Sounds like a mess in ur hands back then.

I rath

Quote:

er have timing Chain than belt so I don't have to worry about belt service every 70k miles or whatever manual says. Plus, I'm just tired of fix fix fix fix engine (done that many times) and I just want to "retire" tho.

Yeah, I wish everything lasts almost forever rather than replacing parts time to time, but it's life.

**sequoias** · 06-10-2009, 09:10 PM

Quote:

Originally Posted by purplecatty

Some V8 or V6 engine have special kit that do not require Belt or Chain, just gears between Crankshaft Timing sprocket and camshaft sprocket which is a modification or 3rd party item. Especially Chevrolet and Ford

Catty

Yes, I am aware that some of them use gear driven timing. I think indy race cars use that method.

The Highlander · 06-10-2009, 09:52 PM

I wish gasoline boxer engine use t-chain.

**sequoias** · 06-10-2009, 09:57 PM

Quote:

Originally Posted by The Highlander

I wish gasoline boxer engine use t-chain.

I wish, too. I was disappointed to find out that Subaru uses timing belt on their engines. I actually thought they use timing chain, but no. I was shocked on the price of the timing belt kit which cost like $200-230 on average for Subaru boxer engines while it costs only under $80 for my car.

The Highlander · 06-10-2009, 10:20 PM

Quote:

Originally Posted by sequoias

I wish, too. I was disappointed to find out that Subaru uses timing belt on their engines. I actually thought they use timing chain, but no. I was shocked on the price of the timing belt kit which cost like $200-230 on average for Subaru boxer engines while it costs only under $80 for my car.

BUT the 3.0L H6 engine use timing chain. The 2.5L H4 engine use timing belt. I forget about H6. Sorry.

Yes, timing belt is very expensive for boxer engine due very WIDE than I and V.

**sequoias** · 06-10-2009, 10:31 PM

Quote:

Originally Posted by The Highlander

BUT the 3.0L H6 engine use timing chain. The 2.5L H4 engine use timing belt. I forget about H6. Sorry.

Yes, timing belt is very expensive for boxer engine due very WIDE than I and V.

Yea, I heard that the 6 cylinder uses timing chain, weird.

deafsmogtech · 06-10-2009, 11:49 PM

Quote:

Originally Posted by sequoias

I have heard of timing chains that can be very costly to repair if it becomes loose as the chain stretchens. That is much more expensive than belt driven engines. Belts rarely stretch while chains do sometimes. It varies on the design of the engines and the manufacturers.

Most Hondas are interference engines (which is why I'm worried), some Toyotas, etc. Chrysler is the only company that has avoided making interference designed engines.

yes, Hondas, few times I worked on the heads (bend valves)' subleted to the machine shop for valve job.
The noise timing chains in SOHC or DOHC engines are expensive repairs than the OHV engines. The common noises are locating in the right bank sides(passenger side) of the V6 or V8 engines (V10?). The loose chains look like 10 speed bicycle when you pedal and notice loose chain on the bottom than upper chain same as the SOHC or DOHC engines.
My last timing chain job was a 1998 Infiniti Q45 w 4.1L DOHC V8 in 2002 at Chevron station for noise chain in right bank side. Fix chain was involved the entired engine/tranny removal by lift the car and drop the engine/tranny. cylinder heads needed to removal to access the chains and guides/tensioners. It took 20 hours labor. The price tag for chain job was $4k. Customer's mechanical insurance took a care of it. $4k lot of money, I made good money sheesh. This chain job is not for a novice mechanic even a Saturday mechanic.

deafsmogtech · 06-10-2009, 11:52 PM

Quote:

Originally Posted by sequoias

Yea, I heard that the 6 cylinder uses timing chain, weird.

Chevy TrailBlazer have timing chain in 6 inline engine

deafsmogtech · 06-11-2009, 12:05 AM

Quote:

Originally Posted by sequoias

Are you aware of them becoming loose because deaf people can't hear that?

That was happen to my deaf customer who brought her a Toyota Camry for oil
change. My tech informed me that he heard noises in timing belt then informed her. I can't hear it but I use a long driverscrew to pinpoint the engine, feel the handle of driverscrew to see if feel funny as driverscrew to be move to another place to compare the feelings. If strange, I call my tech to hear it for me. One problem is I can't detect the low noises with my driverscrew. I have fuel injector test gun with LED blinks to probe injector to see the blinks and can be use it for noise areas.

deafsmogtech · 06-11-2009, 12:07 AM

Quote:

Originally Posted by sequoias

Are you aware of them becoming loose because deaf people can't hear that?

Quote:

Originally Posted by diehardbiker

I no want deal with timing belt. Have had timing chains on all my vehicles and have zero problem whatsover.

Hope you have zero plms on all the OHV engines.

**sequoias** · 06-11-2009, 12:12 AM

Quote:

Originally Posted by deafsmogtech

Chevy TrailBlazer have timing chain in 6 inline engine

Wasn't talking about that...was talking about Subaru's boxer engine.

**sequoias** · 06-11-2009, 12:15 AM

Quote:

Originally Posted by deafsmogtech

yes, Hondas, few times I worked on the heads (bend valves)' subleted to the machine shop for valve job.
The noise timing chains in SOHC or DOHC engines are expensive repairs than the OHV engines. The common noises are locating in the right bank sides(passenger side) of the V6 or V8 engines (V10?). The loose chains look like 10 speed bicycle when you pedal and notice loose chain on the bottom than upper chain same as the SOHC or DOHC engines.
My last timing chain job was a 1998 Infiniti Q45 w 4.1L DOHC V8 in 2002 at Chevron station for noise chain in right bank side. Fix chain was involved the entired engine/tranny removal by lift the car and drop the engine/tranny. cylinder heads needed to removal to access the chains and guides/tensioners. It took 20 hours labor. The price tag for chain job was $4k. Customer's mechanical insurance took a care of it. $4k lot of money, I made good money sheesh. This chain job is not for a novice mechanic even a Saturday mechanic.

Four thousand bucks just to fix that timing chain issue? 0.0

deafsmogtech · 06-11-2009, 12:22 AM

Quote:

Originally Posted by Milwaukee

You go to Lowes or Harbor Frieght for cheap tools.

get those electric impact wrench IT WORTH. We have air impact wrench but I choose electric why no deal with air hose.

You get manual book that show how to do that.

That what I did when I replace timing belt on geo first time.

Fk electric 1/2 drive impact tools. I hate to tell you that Im against all electric impact or drill tools cuz of fire hazard or explosive. If you work inside the shop or garage that is insufficient vent, what happen to gas container or fuel leak from under the hood? Use it outside is fine no plm.
No electric impact tools allow in gas station, no one use them. Safety reason. You be careful with any fuel vapor, I bet you have common sense.

deafsmogtech · 06-11-2009, 12:28 AM

Quote:

Originally Posted by sequoias

Wasn't talking about that...was talking about Subaru's boxer engine.

oh, I have no idea on newer gasoline Subaru boxer engines.

deafsmogtech · 06-11-2009, 12:30 AM

Quote:

Originally Posted by sequoias

Wasn't talking about that...was talking about Subaru's boxer engine.

Quote:

Originally Posted by sequoias

Four thousand bucks just to fix that timing chain issue? 0.0

replaced tensioners, guides, chains and gaskets etc

06-09-2009, 10:01 PM	#1 (permalink)
sequoias Premium Member Join Date: Jun 2004 Location: Iowa, the land of the cornfields and pigs Posts: 21,856	Which do you prefer=timing chain or timing belt? I would like to bring up to debate about timing chain and belts. In my views, I prefer timing chain because of reliabity and less worrying about it breaking suddenly like the timing belt usually do if you negect the service schedule. The timing chain will make some noise which will tell you that it is time to replace it soon, while timing belt doesn't....it does that like a ticking time bomb which is silent surprise. Plus, I hate how many car companies design their engines which piston and valves are close to each other, if it breaks...they crash into each other and end up with a costly engine replacement. I'm currently worrying about it breaking because I'm already at 90k miles and it needs to be serviced soon and it is pretty expensive which costs $395 for the 90k mile service, I can't afford that right now and hopefully will do that next month as I'm going to work 24 hours on Sat and Sunday this weekend and hopefully get more extra work later this month and next month.

06-10-2009, 06:05 AM	#5 (permalink)
diehardbiker Registered User Join Date: Mar 2004 Location: In back of Superduty Posts: 11,249	I no want deal with timing belt. Have had timing chains on all my vehicles and have zero problem whatsover. __________________ J-MAC's quote: "People who try and fail are more superior than people who don't try at all" "If people let the government decide what foods they eat and what medicines they take, their bodies will soon be in as sorry a state as the souls who live under tyranny." Thomas Jefferson (1778) Avatar picture is Cape Hatteras light house in OBX.

06-10-2009, 03:20 PM	#11 (permalink)
Foxrac Need Stormtroopers? Join Date: Mar 2005 Location: Zaphias Posts: 32,472	I prefer timing chain, that what Chevy truck has timing chain with V8. Timing chain is hardly need replace but I wish that engine need be designed for last longer without worry about need replace, I can learn to change the parts in car if I want too. __________________ In Moto We Trust

06-10-2009, 09:52 PM	#18 (permalink)
The Highlander Registered User Join Date: Mar 2007 Posts: 6,229	I wish gasoline boxer engine use t-chain. __________________ "There are a lot of people that don’t like this software. It is because they don’t understand how to use the software and don’t realize it’s potential."

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06-09-2009, 10:09 PM	#2 (permalink)
Babyblue Registered User Join Date: Dec 2007 Location: Florida Posts: 11,999	I never had a timing belt, break on me. I do not know if my current vehicle, have a timing chain or belt.

06-09-2009, 11:08 PM	#3 (permalink)
Milwaukee Registered User Join Date: Apr 2009 Location: Trenton, MI Posts: 335	I have replace timing belts on geo storm I am supposed to change my timing belt on 94 geo tracker 5,000 more miles then I change. new timing belt cost $25 tension pulley cost $50 water pump $40 That all what I need to do. For me I rather have timing chain but geo doesn't came with that so it

06-10-2009, 11:51 AM	#9 (permalink)
Milwaukee Registered User Join Date: Apr 2009 Location: Trenton, MI Posts: 335	You go to Lowes or Harbor Frieght for cheap tools. get those electric impact wrench IT WORTH. We have air impact wrench but I choose electric why no deal with air hose. You get manual book that show how to do that. That what I did when I replace timing belt on geo first time.

06-10-2009, 07:13 PM	#14 (permalink)
purplecatty Registered User Join Date: Feb 2007 Location: Center of the USA Posts: 3,609	I prefer Timing Chain. Even though I never had Timing Belt breaks on me. Currently, My Durango and Jeep uses Timing Chain. If Timing chain became stretched, I would replace that myself otherwise, either one would have been sold to another owner 1989 Mazda 323 use Timing Belt. I don't have issue with that but it's the space between right frame and engine where timing belt located. The water pump pulley was the toughest part and I had to use 10mm monkey wrench to loosen 4 bolts on pulley before I take covers off because it gave me only 1 inches clearance. Once the cover and Crankshaft pulley is off (crankshaft pulley was the easiest cuz it have 6 bolts holding main pulley and I loosen it first then use my power drill with 10mm socket on adapter to make job real quick). It took me 30 min to do Timing belt replacement. I don't replace timing belt on Mazda often, I let it go way past it's timing belt service mile cuz if timing belt breaks, the engine won't get damaged cuz of piston and valve have its clearance whether it's open or close. Out of 225,000 miles on Mazda 323, I only replace twice. Same goes for 1990 Mazda Protege, I only replaced once. My 1967 Chevy C-10 Pickup truck had it's timing sprocket sheared off cuz it's nylon teeth on main crankshaft behind the cover. The shop that rebuilt the truck before they sold it to me use cheap timing sprocket. I decide not to bother replace timing sprocket. I simply replace engine cuz original engine was full of grease and oil and it's really dirty. I replaced it with 1977 Camaro modified engine (305 block with 350 head). I rather have timing Chain than belt so I don't have to worry about belt service every 70k miles or whatever manual says. Plus, I'm just tired of fix fix fix fix engine (done that many times) and I just want to "retire" tho. Catty