Can anyone tell if a 5th Gen tach is a v6 or v8 version by it's outward appearence? I have one with a redline starting at 5k rpm and I've seen some that have a redline starting at 4.5k; which is which?

Thanks very much ! 8)

My v8 tach starts at 5 K to 6k.

Hey TOMMY ! Thanks a "Million" for the info! I noticed in your tiny profile picture your truck looks like it's lowered, is it? Can you email me any pictures of it ? I sure would appreciate any tech tips from you or anyone reading this about do's & don'ts on lowering 5th gens. 8)

cbeal@cybermesa.com

Dude, Check out my gallery link. You will also see a pic of the gauges. My rear has stock springs & air lift bags. The front is lowered 1 1/2 with springs. I run kyb gas adjust shocks all around. Huge difference. Also go to the suspension section. We have posted a lot of info. there. I you have a specific question, please ask.

Can anyone tell if a 5th Gen tach is a v6 or v8 version by it's outward appearence? I have one with a redline starting at 5k rpm and I've seen some that have a redline starting at 4.5k; which is which?
The red line is not an indication of V6 or V8 application. The 4.5K red line tach (with the clock in it) was used up until 85. The 5K red line tach was used in 86-88.

This is one of those questions that nobody seems to have an answer for. I'm not sure if there is a way to tell from the outward appearance. There was only one RPO for the tachometer U16. There wasn't one RPO for a V6 tach and another RPO for the V8 tach. Maybe we'll never know. I think I'll dig into the parts manual tonight and do some research.

HEY EARNIE! Thanks for the input, I sure appreciate it! I have a used tach and I think it's '86-'88 (might even be Monte Carlo) and it doesn't have a clock, just #'s 1 thru 6. The redline starts at 5. I saw a '86-'88 on eBay for sale with a redline starting at 4.5 so I kinda suspect it's a six cylinder application, but again, don't know for sure.
Thanks again for your comments! 8)

My original 78 tach did start at 5k & never had a clock. When I installed the white stickers I went to the later model stickers cause they looked better. Mine has the U14 gauge & tach option.

After some extensive research I've found out quite a few things about some of the 5th generation tachometers. Here are the part numbers for the 86-88 tachometers by engine designations.

Monte Carlo SS - 305G - 25059057
El Camino - 305H - 25059056
El Camino - 4.3Z - 25059055

For 86-88 there were two V8 tachometers and one V6 tachometer. I did a search for these part numbers at http://www.gm-parts-dealer.com and found that the MCSS tach and the V6 tach are still available. However, the description for the MCSS tachometer now says El Camino instead of Monte Carlo. Amazingly enough, they both cost under $100.

There were also several different 78-85 V8 and V6 tachometers....

Unfortunately, the bulb in my microfiche reader just burned out and I'll have to continue this thread later...... :-(

Boy Ernie, talk about a lending hand! Thanks very much for the research and your time. I really appreciate your efforts! GOOD INFORMATION!! :D